eRouška's contribution to the fight against the pandemic is over

Ministry of Health of the Czech Republic decided to pause the development of the application starting October 2021.

From a long-term perspective, eRouška helped to manage the epidemic by notifying more than 400,000 users about risky encounters and by recommending safety measures.* After it was connected to the European gateway, it communicated with similar applications from other EU countries and watched over risky encounters with foreigners in the Czech Republic and abroad.

Thank you for joining more than 1.7 million people and helping to protect people around you.

When the app was paused, it was active on about half a million users' devices. However, only dozens of people would enter information in it every day. Its use did not increase even after the number of infected individuals rose in September and October. It is probably due to the fact that most eRouška users (technically advanced users who are interested in helping to protect public health) are vaccinated. Tracing is not the only tool for managing the epidemic anymore. There are general measures, vaccination and other tools such as the "O-T-N" certificates (vaccination, testing, history of covid) and Tečka and čTečka applications.

* Note: From October 2020 to August 2021, about 1.7 million people with risky encounters were quarantined via phone tracing. Therefore, over 400,000 notified potential contacts were an important addition to phone tracing.

What will happen next to eRouška and logged data?

Starting at the end of October 2021, eRouška is switched to an "inactive" version. If you keep it on your device it will not run on the background and consume energy. Deactivated eRouška will support push notifications so that we can notify you in the future. Logged data in the Apple/Google Exposure Notification API in you device will be automatically deleted within two weeks after the deactivation of Exposure notifications. You can also manually delete the data anytime.

Server settings are documented and backed up. All aggregated anonymised user data were deleted before October 31, 2021. eRouška's source code (both mobile and server parts) are licensed as open-source and freely accessible at

If the epidemiological situation calls for a reactivation of eRouška, the NAKIT can release an update which will allow users to reactivate eRouška.

What should I do when the application notified me about a risky encounter with an infected user?

If you have symptoms of infection (e.g. high temperature, cough, stuffiness, sore throat, headache, or a sudden loss of smell or taste), call your general practitioner. In case of an emergency, call 155 for an ambulance or 112 for the integrated rescue system. The mentioned symptoms may appear between 2 and 14 days after the risky encounter.

If you have no symptoms please act responsibly:

  • Wear a mask or respirator over your mouth and nose.
  • Wash your hands with soap thoroughly and use hand sanitizer regularly.
  • Sanitize your personal belongings (e.g. your mobile phone) regularly.
  • Cough or sneeze into a tissue or your sleeve.
  • Use disposable tissues and throw them away after use.
  • Avoid unnecessary large group gatherings and keep a safe distance (approximately 2 meters).

If you receive a notification in eRouška and suspect that you encountered an infected person, call your general practitioner and follow their instructions. It is also possible that a public health officer will contact you after epidemiological investigation with the infected person. In that case, follow the officer's instructions.

If your health deteriorates within 14 days after the risky encounter and you experience COVID-19 symptoms, contact your general practitioner.

What shall I do when I am positive for COVID-19 or I received an SMS with a verification code for eRouška?

If you received and SMS from the laboratory saying you are positive for COVID-19, you should also receive another SMS with the eRouška verification code within a few hours. eRouška messages are sent automatically after your results are saved in the information system. Automated processes of the Smart quarantine cannot influence the moment when the laboratory sends the results to the information system.

If you receive an eRouška SMS message with a verification code, please follow these instructions. This will allow you to anonymously notify other users about the risky encounter. Thank you!

Have you tested positive but have not received the eRouška SMS? Request your code at

So every time the app says that I was in contact with and infected person, I will have to stay in quarantine or get tested?

No, eRouška is fully anonymous, using it is voluntary and a risky encounter is not a reason to enforce quarantine. If a person is tested positive, they will be contacted by the public health office to find out who they encountered in the previous days. If that person uses eRouška they can contact even those who they do not know, such as fellow passengers on a bus. By entering the verification code, they can send out notifications to all other eRouška users who they encountered in a risky manner.

When the app notifies you that you have encountered a person tested positive for COVID-19, you should follow the recommendations. If you experience health problems contact your general practitioner immediately.

Will eRouška find out if I break my quarantine for example by going to my cottage?

The application doesn't track your location – it's not its purpose – and it's not designed for it either. It will not find out if you have broken your quarantine or where you have gone. On the contrary, it should help to quarantine only people with a confirmed infection or suspect cases.

Can eRouška issue a sick leave note for me? Is the exposure notification a reason for incapacity for work?

No, it cannot and it is not. If eRouška displayed the notification, follow the recommendations. Exposure notification does not substitute a report from your general practitioner or a laboratory which handles your COVID-19 test results. Only a doctor can issue valid documents that you can send to your employer.

Why is eRouška needed? Can it effectively protect me from the virus?

One of eRouška's goals is to stop further spread of the infection by isolating potentially infected individuals from the rest. It also helps prevent implementing country-wide measures that have a negative impact on the society and economy of the Czech Republic. Similar applications were also introduced in other countries and are an effective tool to fight against COVID-19.

eRouška 2.0 is a complementary application of the Smart quarantine – Ministry of Health's system. Using Bluetooth technology, eRouška connects to other eRouška apps nearby and saves their anonymous identifiers. If a user is tested positive for COVID-19, they will receive an SMS with a verification code which allows the user to send their anonymous identifiers to other eRouška apps. According to the epidemiological model*, other users' apps will then evaluate whether they were in close enough contact to send out notifications and guide users to further investigation. Thus eRouška 2.0 helps to inform other potential transmitters of the infection and to speed up their testing. This decreases the number of infected individuals in the society and the risk of further infections.

* Closer than 2 metres apart and longer than 7 minutes.

What if someone does not admit they are infected?

This can also happen. However, we believe that eRouška users want to actively help stop further spread of the virus, and use the application in order to alert people with whom they've come into risky contact. Intentional spread of COVID-19 is a criminal offence in the Czech Republic.

Is it worth installing eRouška if there are not enough people using it?

This is the reason why you should not hesitate. The more of us use eRouška, the better network to protect us and warn against risk we will create. Help us. You can actively join the fight against COVID-19 by installing the app. You can also tell people around you about it and help them install it.

How does eRouška differ from other similar apps?

eRouška uses Bluetooth technology which is used by most smart mobile devices in the Czech Republic. It works inside buildings, underground parking lots and the Metro. The application is designed not to collect your location information (e.g. via GPS). It only collects anonymous information on which other eRouška users you encountered closely. It is the only application in the Czech Republic that can officially use the Apple/Google protocol which guarantees the app's security on Android and iOD platforms and lowers battery use.

What is the Smart Quarantine? What is the role of eRouška in it?

It is a set of clever measures that protect people from contagion and the economy from collapsing. Instead of keeping the whole nation in quarantine, the Smart Quarantine enables finding, testing and isolating only infected individuals and people with suspected infection.

More specifically, it is a system of management in forecasting, decision support, active contact tracing, testing including sampling point capacity management, laboratories, managing quarantines and related material and IT delivery to contain the pandemic of COVID-19. Smart Quarantine 2.0 is the name for transition of the project under the Ministry of Health which will be able to quickly react to any epidemics in the future thanks to new tools that are being developed.

eRouška application is one of the tools that were developed to support Smart Quarantine. Using technology, we can actively notify risky individuals who encountered an infected person to implement more protective measures, consider voluntary quarantine, and contact their GP in case they experience COVID-19 symptoms. We believe that thanks to these steps, we can contain the spread of the infection and save the health care system from a fatal overload.

How eRouška works

How does eRouška collect and process data about users' encounters?

Your smartphone with eRouška will record anonymous identifiers (ID) from other devices with this application via Bluetooth LE. It stores information about the “encounter” and its length in its internal memory.

If your COVID-19 test is positive you will receive a verification code in an SMS. You will enter it in eRouška (follow these steps) which will send your anonymous identifiers to the server. Other eRouška apps will download them for evaluation. The algorithm in each eRouška will automatically evaluate the data within the epidemiological model: it will compare the identifiers with all logged encounters. For each risky encounter, the app will display a notification, warn the user that they might be potentially infected, and recommend further steps.

You can find detailed information about data collection and processing in Information about personal data processing in eRouška 2.0.

How does eRouška evaluate risky encounters?

Originally, epidemiologists established that a risky encounter is one that takes place closer than 2 meters apart for more than 15 minutes. However, aggressive transmission of new coronavirus mutations shows that even a shorter encounter might be risky.

We consulted Apple/Google and other countries on next steps regarding more aggressive mutations and we are gradually changing the parameters of risky encounter evaluation, beginning in March 2021. We periodically evaluate their effect on the number of risky encounters. These days, we are adjusting the time parameter, which is currently set to about 7 minutes.

eRouška strives to evaluate the parameters of distance and length of encounters as precisely as possible with the current technology. The distance between app users' phones is estimated by Bluetooth signal strength. The length of an encounter is considered periodically: every few minutes, the phones search for other phones with eRouška nearby.

The precision of these parameters is technologically limited. The bigger the distance and the shorter the encounter is, the more difficult it is to evaluate it. Loosening the parameters of evaluation thus increases the probability of false positive and false negative results.

A higher precision requires more frequent logging of other devices with eRouška nearby. Unfortunately, that results in a higher energy consumption. Measurement algorithms are set up by Google and Apple in their Exposure Notification protocol on which eRouška is built. eRouška developers can only partially change these parameters and filter on the results. You can find more explanation in Risk evaluation.

How does eRouška react to new variants or mutations of the virus?

New virus variants that have appeared since the pandemic started are examined regarding their infectiousness and health impact. eRouška developers are in close contact with both Czech administration and Apple and Google that provide the exposure protocol. Therefore, they are able to alter the evaluation algorithm when the risk of infection changes due to research advances.

What if eRouška misinterprets a contact with another person who is, for example, in a car at a crossroads, behind a door or a thin wall?

eRouška works by measuring the signal strength between two devices. Technically, it cannot be ruled out that a false detection occurs. You can read more about technical limitations, risks of app use and the process of encounter evaluation on Reliability of risky encounter evaluation and on Technical requirements in Terms and conditions.

In order to evaluate the contact as risky, it is important to measure the distance (under 2 m) and length of contact (several minutes) – therefore stopping at traffic lights is insignificant.

I received an exposure notification, but eRouška shows that it has not logged any risky encounter near me.

If the notification with red virus icon and text Exposure notification (Android) or Exposure log (iOS) surprised you, no need to worry. It is only a system notification on Android and iOS which eRouška cannot influence. View this picture which shows what eRouška notification looks like.

You can find out whether you encountered an infected individual on the main page of eRouška.

If you saw a risky encounter in eRouška which then disappeared, it is possible that the evaluation parameters have changed in the Android app update so eRouška does not consider that encounter to be risky anymore.

So everyone will know I have COVID-19?

No, they won't. If you are tested positive, your identity is only known to the public health officer. People that received a notification about a risky encounter will never know who, where or when they could have been infected. The application only displays the general information about risky encounters and recommends further steps. Your identity is safe.

I was tested for COVID-19, but I still have not received the SMS with the verification code for eRouška. When can I expect it?

First, you will receive test results in an SMS from the laboratory. The lab also sends the results to the central information system of the Ministry of Health. After the results are copied to the public health office's system, automatic eRouška SMS messages with verification codes are sent. If the lab does not send the results to the information system on the same day, you might not receive the SMS with the verification code until the next day.

Please check that the eRouška SMS was not blocked by the system as spam by mistake

  • Android: In your Messages app press the options icon (three dots) and Spam and blocked conversations (or three dots → Settings → SIM → Spam). If eRouška SMS is there, click on Not spam.
  • iPhone: Go to Settings → Messages → Blocked contacts. Here you can manage the list of blocked contacts and phone numbers. Please check that you do not filter unknown senders in Settings → Messages → Unknown and spam.

If you do not receive eRouška SMS even the day after you received an SMS confirming your infection from the laboratory, send us a message to asking for a new SMS code. Please state the following information:

  • full name on your test request form,
  • phone number on your test request form,
  • date of test results,
  • sampling address / laboratory which handled your test results,
  • test type (PCR/antigen).

Will I receive the code in an SMS if I tested positive in an antigen test?

If your antigen test results positive and you experience COVID-19 symptoms (stated in the request form), you will receive the eRouška code in an SMS same as in a positive PCR test.

If your antigen test is positive but you do not experience COVID-19 symptoms, you will undergo a PCR test. If that results positive, you will receive the code in an SMS. If your PCR test is negative, you will not send your data from eRouška.

In which countries can I use eRouška? How does cooperation with foreign apps work?

European Commission developed a central gateway service for a secure information exchange (EFGS). This gateway allows eRouška to exchange warnings with other tracing applications used in various European countries. You can find more information about the gateway in Coronavirus: EU interoperability gateway for contact tracing and warning apps – Questions and Answers.

If you want to view more information on joined countries and settings, tap Cross-border cooperation on the home page in the app. You can enable or disable the feature and view the list of countries. You can find the official list of EU countries at European Commission's website.

Does eRouška use Apple/Google API?

The new version eRouška 2.0 for Android and iOS uses Apple/Google Exposure Notification API. Remember to update your eRouška app in Google Play (Android) or App Store (iOS) and activate it again.

What is Apple/Google Exposure Notification API (protocol)?

Together, Apple and Google develop technologies which can be used by public health institutions (Ministry of Health) to develop national applications for tracing risky encounters with individuals with COVID-19.

It is an interface which allows specific apps (eRouška in the Czech Republic) to reliably access system tools of Android and Apple devices and log encounters – mainly to use Bluetooth LE to verify the contact and run in the background without any more settings of the app or the operation system. Encrypted communication protocol then ensures a safe transmission of current lists of identifiers of infected individuals between tracing applications in order to evaluate risky encounters and send notifications.

Find more information directly on Apple and Google websites.

Where in eRouška can I find information on stored encounters?

eRouška 2.0 is built on Apple/Google Exposure Notification protocol which manages a secure storage and evaluation of encounters. Due to security reasons, it does not let the app directly access the data of encounters.

On the main screen, you can see whether the app is working correctly. Information about stored encounters is saved in the system. However, these encounters might not be the risky ones. You can find them in Settings:

  • Android: Settings → Google → COVID-19 Exposure Notifications → press three dots in the upper right corner → Exposure Check
  • iOS: Settings → Exposure Notifications → Exposure Logging Status → Exposure Checks

What are the records in Settings → Exposure Check?

Recording contacts with the infection show how many keys from infected users were downloaded on your phone from the server and how many of those match those that your phone logged.

Exposure Check: Date and time when keys were downloaded from the server in the past 2 weeks. To view more you need to open individual records.

iOS: Provided Key Count: Number of keys from users who tested positive. Your phone downloaded these keys on that day to check for possible encounters with infected individuals.

iOS: Matched Key Count: Number of downloaded keys paired with keys found near you. If this number is higher than 0, you have encountered an infected individual. That does not necessarily indicate that it was a risky encounter.

Android: Number of keys: Number of keys from users who tested positive. Your phone downloaded these keys on that day to check for possible encounters with infected individuals.

Android: Number of matches: Number of downloaded keys paired with keys found near you. If this number is higher than 0, you have encountered an infected individual. That does not necessarily indicate that it was a risky encounter.

Timestamp: Date and time of the check. It is not the time of a risky encounter (the time is missing to protect the users' privacy).

Data source: Application that checks and evaluates risky encounters.

Hashing code: Check sum of the file that contains keys from infected users. Until the file contents change, the check sum will not change during the 2-week period.

How will I know that eRouška works on the background? Why don't I see the app icon in the status bar?

We removed notification icon because storing and evaluation of encounters is done by Apple/Google protocol in the system. The app is responsible for downloading keys (identifiers) of infected users once or twice a day and does not need to run permanently.

You can view the app status on its main page. You can then check that the keys were downloaded in the Settings:

  • Android: Settings → Google → COVID-19 Exposure Notifications → press three dots in the upper right corner → Exposure Check
  • iOS: Settings → Exposure Notifications → Exposure Logging Status → Exposure Checks

Why does the date and time of "Last data update" on the main page of eRouška differ from date and time of "Exposure Checks" that I can see in Settings?

eRouška shows the date and time of the last successful attempt to check new keys (identifiers) of infected individuals on the server. Phone Settings show date and time when the keys were last found and evaluated.

Keys of infected users download once or twice a day.

Why can't I view the exact time of a risky encounter in eRouška?

eRouška is built on Apple/Google Exposure Notification protocol which manages logging and evaluation of encounters in the operating system. Apple/Google protocol allows eRouška to access only the date of a risky encounter so that the privacy of users is ensured.

Why do I see "Found keys: 0" in Exposure Checks in the phone Settings?

It means that Apple/Google API in your phone has not evaluated any encounter with an infected individual. In other words, downloaded keys of infected users on a given day do not match keys stored in your device.

Why do I see keys for specific dates in the phone's Settings > Exposure Checks but eRouška does not display any risky encounters?

The number of keys indicates the number of logged encounters with infected individuals. However, they might not be risky encounters. If an encounter is not risky, eRouška will not notify you about it. That's why you cannot see it in the app.

I received a notification about a risky encounter that took place several days ago. Why did eRouška only notify me now?

eRouška cannot evaluate risky encounters and display notifications before the user with a positive test sends data from their eRouška. If today you receive a notification that you have encountered an infected individual several days ago, it means that the person only sent their data today or yesterday. Your eRouška downloaded and evaluated the data today.

I received a notification about a risky encounter, but I can see several logs with various dates on the Risky encounter page.

eRouška evaluated risky encounters after a user who tested positive for COVID-19 sends data from their eRouška. If you received one notification but there are more logs on the Risky encounter page, it means that you have met that person more than once or that more than one user sent their data on the same day.

Will eRouška work as a "covid pass" for test results and vaccination certificate?

eRouška is anonymous so this feature does not allow it to cooperate with Digital Green Certificate which uses a verified identity and personal data of the user such as test results or vaccination certificates.

Does eRouška publish app usage statistics?

We publish statistics in JSON format at The data have the following structure:

  "data": {
    "modified": 1608696001,
    "date": "20201223",
    "activations_yesterday": 2042,
    "activations_total": 1475571,
    "key_publishers_yesterday": 718,
    "key_publishers_total": 39175,
    "notifications_yesterday": 631,
    "notifications_total": 197298
  • modified = Unix timestamp of generated statistics,
  • date = date of report created,
  • activations_yesterday = number of activations on the previous day,
  • activations_total = total number of eRouška activations,
  • key_publishers_yesterday = number of infected individuals who entered the code on the previous day,
  • key_publishers_total = total number of infected individuals who entered the code,
  • notifications_yesterday = number of individuals who received the notification about a risky encounter on the previous day,
  • notifications_total = total number of individuals who received the notification about a risky encounter.

A call without a parameter will display current day's information. A call with parameter date will allow you to get data for any day after October 23, 2020 (we only have aggregated data before then). Using parameter date with value all, you can get all data that the interface provides.

Installation and compatibility

For which phones is eRouška available? Why are the requirements stricter than in eRouška 1.0?

To install eRouška, you need a mobile device with the following parameters:

  • iPhone with iOS 13.5 and higher
  • OS Android 6.0 and higher with Google Play Services (only a small percentage of Huawei phones and some phones with their own ROM do not have this)
  • Bluetooth LE (Low Energy)

If your phone is not compatible with eRouška (it does not have the necessary features) Google Play Store or Apple App Store will not let you install it. The application is available only for some Android tablets. It is not available for iPads.

Apple and Google define the minimum requirements of compatibility. They are based on the Apple/Google Exposure Notification protocol which the new eRouška uses. We decided to start using the Apple/Google protocol to make sure that the app works on iPhones and to be compatible with similar applications in other European countries.

Where can I safely download and install eRouška?

eRouška is only available for:

Is it possible to download the application outside official application stores? Is an apk available?

eRouška 2.0 uses Apple/Google protocol to log encounters and transmit data. Therefore, it depends on system services, without which it would not work, so it is not possible to install it from other than official app stores. Application stores will automatically filter for compatible devices.

eRouška developers never provide users with links for installation packages (APKs) or installation files outside official application stores. We would not be able to guarantee security, updates or user support for unofficial app installs. Please, do not download eRouška from .apk files that you find online or receive by email. They might contain viruses, trojan horses or other harmful content.

Can I use eRouška with another tracing application of a foreign country (e.g. Corona-Warn-App)?

If you spend most of your time in the Czech Republic, we recommend to use eRouška to travel abroad as well. eRouška now cooperates with other EU countries.

In other cases, you can install more tracing apps along eRouška, such as Corona-Warn-App, Stopp Corona App, Imunni, Stop Covid ProteGO Safe etc. However, if they also use Apple/Google Exposure Notification protocol (especially in neighbour countries), only one of them can be active at any given moment. You would need to pause the others. Only one app can access the Apple/Google protocol's logging feature at the same time.

Does eRouška work when I use a battery saver?

iOS: When using a battery saver, app updates and automatic downloading in the background are limited. eRouška scans nearby devices and logs encounters, but does not evaluate risky encounters.

Android: Battery savers on Android devices might significantly limit applications running in the background. Although the system for risky encounter notifications still works, the evaluation might be paused and notifications might not be displayed.

Will I be able to use eRouška on smart watches or smart wristbands?

This might be possible in the future. Right now, we are not developing this because the smart watch or wristband would need to support Bluetooth LE (Low Energy) and Apple/Google protocol. Basic Bluetooth without LE only manages data transmission but cannot measure the intensity of user encounters via signal strength.

Connection and data transmission

Do I need to keep Bluetooth turned on all the time?

Yes, you do. Without Bluetooth turned on, it is not possible to detect nearby devices with eRouška. You may have already enabled Bluetooth if you use wireless headphones, a smart watch or a connection with your car. We recommend you to set Bluetooth to be visible for all devices.

Does eRouška need internet connection?

Internet connection is necessary to download (install) and activate eRouška. It also needs internet connection to download anonymous identifiers of infected users every day and display notifications about risky encounters.

If you are tested positive for COVID-19 and would like to anonymously notify others of a risky encounter, you would have to connect eRouška to the internet. Until then, your data is saved only in your phone's memory and is deleted every 14 days. The application also uses internet connection to download information about the epidemic's current development in the Czech Republic which is displayed on the News page.

How often does the app update online data?

eRouška downloads keys (identifiers) of infected users several times a day. Statistics on the News page are updated once a day.

How much data does eRouška consume daily?

If Notifications about foreign risky encounters is enabled, eRouška will also download keys of all infected individuals from other EU countries. The volume of downloaded data may be up to 2 MB daily.

Even if Notifications about foreign risky encounters are disabled, eRouška downloads about 1 MB of data every day. The new app version downloads keys not only from eRouška users, but also from infected users from other EU countries who indicated that they were travelling abroad and whom an eRouška user might have encountered.

Keys of infected individuals are downloaded 2–3 times a day. To compare, an average web page requires about 1–5 MB of data. The application does not necessarily need mobile internet. It can download data when connected to WiFi.

Android: Why do I need to allow the application to access GPS/location data?

Update for Android 11 users: You do not need to enable location services for the newest Android operating system versions for eRouška to work.

eRouška does not collect or store GPS data, but the operating system Android 10 and older also includes some Bluetooth LE (LE = low energy) services, which eRouška components need in order to function properly – specifically, Google Play Services. Therefore, the user's consent to the application's access to location data is required. This consent is not required on iOS. Google explains why location services must be enabled in the phone.

Other applications in your phone might use information on your location. If you want to check which apps use your location, go to your phone's settings → Location → App permission (or follow these steps by Google). You can deny location permission to other apps if you think they do not need it. eRouška does not need it so it will not be listed.

How much battery do Bluetooth and eRouška app drain?

If you already use a phone with Bluetooth enabled, power consumption should not increase significantly. If you do not actively use Bluetooth, the results of our testing where Bluetooth was turned on all the time showed that energy consumption increased by units of percent per day. In most cases, it is less than 20% of battery capacity per day. It depends on the specific smartphone, your style of use and battery condition.

Power consumption related to eRouška use is affected by 2 factors. First, it's the application itself, and second, it's the use of the system's Exposure Notification which regularly logs encounters with other eRouška users. The system function is provided by operating system Android or iOS so its optimization depends on updates from Apple and Google.

When interpreting power consumption, please consider that this percentage depends on your phone's full use during the past 24 hours (proportion of use by other apps). That means that the percentage of eRouška use might be high in low-use phones, while it might be low in highly used phones. So it does not show the percentage of battery use.

Android: Note for location services: It is only possible to detect a Bluetooth device near you if you enable "Use location" in the settings. (Read more in Why your phone’s location setting needs to be on? on Google's help page.) It means that other applications in your phone might use information on your location, which might be the reason for a higher power consumption. Please check which apps use your location. Go to your phone's settings → Location → App permission (or follow these steps by Google). You can deny location permission to other apps if you think they do not need it. eRouška does not need it so it will not be listed.

Is it possible that after turning on eRouška, my Wi-Fi or internet connection slowed down?

Unfortunately, some Android mobile phones' Bluetooth negatively affects Wi-Fi signal and vice versa.

Can eRouška cause problems with other apps or devices that use Bluetooth (headphones, watches, wristbands)?

Very rarely, users might experience strange behaviour of their Bluetooth devices after they install eRouška, such as connection interruptions, typically in smart watches or wristbands, wireless headphones or handsfree sets. Most probably, it is an operating system issue which we are not able to affect.

Please try to apply the following steps:

  1. Restart your phone.
  2. Unpair your Bluetooth device and pair it again.

If these steps do not help please contact your device's manufacturer:

Why does the app use Bluetooth? Are there no better alternatives such as GPS or triangulation from phone network operators?

User privacy comes first, and Bluetooth technology offers the best balance between logging accuracy and maximal privacy. Neither GPS technology nor operator triangulation can provide necessary data with the required accuracy. Among other things, it is because their functionality inside buildings or metro is very limited. eRouška needs to know that an encounter has occurred, at what distance and its duration. It does not matter where the encounter took place.

Is Bluetooth a secure enough technology?

Bluetooth is a widely spread standard for connecting mobile devices with other devices such as wireless headphones, speakers, smart wristbands or smart watches. Since Apple and Google have developed the common protocol only for national Bluetooth LE-based contact tracing mobile applications, we are convinced that it was the right choice for eRouška as well. However, it has to be said that each and every technology has vulnerabilities. That is why we recommend our users to regularly update their apps as well as the operating system. The OS updates often contain important security patches.

Data security

How do I know which data the application stores and sends?

eRouška application 2.0 uses Apple/Google Exposure Notification API which allows for collecting data and transmitting identifiers among users. Thanks to that, the application does not have a direct access to logged data which could be displayed to users, as it did in the previous version 1.0.

The app downloads a list of identifiers from users who tested positive on a daily basis. Only the user can send data with identifiers to others, and only after they enter the SMS code that they will automatically receive when they test positive for COVID-19.

The app will then send anonymous aggregated statistical information that individuals in risk were notified. This information is not connected to any user or phone identifier and is only used to calculate statistics about eRouška's efficiency.

To make sure eRouška works correctly, we collect data such as crashes and app usage on your phone. We use standard tools (Firebase Crashlytics and Google Analytics) developed by Google. Telemetry sent into these tools does not contain any data about you or your phone.

You can find detailed information about data collection and processing in Information about personal data processing in eRouška 2.0.

Will eRouška data be copied after I perform phone recovery or if I get a new phone?

To protect your privacy, neither Android nor iOS back up data from Exposure Notifications. If you reinstall your phone's system or get a new phone, the stored identifiers will not be recovered.

If you want to receive the information about a possible risky encounter, we recommend you check your old phone over the period of 14 days after you install eRouška on your new device. It is necessary to:

  • make sure that your device is turned on and connected to the internet so that it can download evaluation data,
  • open eRouška on your old device at least once a day.
  • If you test positive during these 14 days, please enter your code in the new device. To receive the code for your older device, please contact us at

After 14 days, your old phone will not contain any data useful for risky encounter evaluation. You can uninstall eRouška from it and keep the app only in the new device.

What if my phone is stolen or I lose it?

Only anonymous information about other devices detected by eRouška is stored in the app. This does not bring any risk to you or the owners of other devices. Other applications that you commonly use may store much more sensitive data on your phone. Keep your phone protected with a passcode or biometrics (fingerprint or face).

Is eRouška compliant with GDPR?

The entire system of the application eRouška including the website is designed in full compliance with GDPR and the Personal Data Processing Act.

You will find more detailed information here:

How do you protect users from data abuse?

We protect users primarily by minimizing the range of logged data and storing them directly in the device. User data is not sent or processed anywhere without their knowledge and consent. The app stores only anonymous identifiers (IDs) of other eRouška users and information about the time, length and Bluetooth strength. Data is automatically processed on the server only after they are sent by the user.

Does an independent organization oversee the security of application data?

The whole system of eRouška application including the supporting website is developed in full compliance with GDPR. The application's code is open-sourced (Android, iOS) and underwent an audit by independent education institutions.

You can find more information in Information about personal data processing in eRouška 2.0.

Can someone track my location using eRouška?

No. The application does not collect information about your location and only you have access to the saved data. The data that the app sends after your consent cannot be used to track your location. Moreover, for safety and privacy reasons, eRouška changes its ID regularly to prevent it from being abused.

Can I verify that the app is not recording my location?

Yes. eRouška application is published as open-sourced code (Android, iOS), so an informed person can easily verify that the application indeed does not collect location data.

The source code of eRouška is reviewed by independent authorities who confirm that the application:

  • does not track location
  • does not automatically send data

Can a user's application identifier (ID) be paired with a specific person?

Application eRouška 2.0 does not work with personal data. Generated anonymous eRouška identifiers are sent between the applications and the server via an encrypted communication protocol developed by Apple and Google. Neither users, nor developers or other authorities can access the identifiers.

Who has (could have) access to my data?

Neither the user not any other person can access logged data about encounters in eRouška 2.0. The reason for this is that this app version uses Apple/Google protocol which does not allow access to logged data to users, developers or other individuals. Data (anonymous identifiers of infected individuals) are sent to the server and other users' devices encrypted and are evaluated on the devices automatically if a notification about a risky encounter is needed to be displayed. They are deleted from the devices and the server automatically after 14 days.

How old data is available? When and how is it deleted?

eRouška saves the data for 14 days. Older entries are automatically deleted. If you are tested positive for COVID-19, enter your verification code in eRouška and send identifiers from your phone to the server, the data will stay there for 14 days after which they will be deleted. You can delete data from your phone in Exposure Notification settings. The specific steps differ among devices and operating system versions.

  • Android: On Android devices, uninstalling the app is enough to delete stored keys (identifiers).
  • iOS: On iPhones, stored identifiers are not deleted during uninstallation.

For information about data controllers and processors, see the Terms and Conditions.

Can I change my mind about using the app at any time? Can I delete the data that I send out to be processed?

You can uninstall the application any time you want. You can delete stored identifiers from your phone in Exposure Notification settings. The specific steps differ among devices and operating system versions. Data which were sent to the server are automatically deleted after 14 days.

  • Android: On Android devices, uninstalling the app is enough to delete stored keys (identifiers).
  • iOS: On iPhones, stored identifiers are not deleted during uninstallation.

What happens to the data after I delete the app from my smartphone?

Android: Uninstalling the app is enough to delete stored keys (identifiers) from phones or tablets with Android OS.

iOS: On iPhones, generated and stored keys (encounter logs) are not deleted during uninstallation. Data from the past 14 days remain in the system until you delete them from Settings → Exposure Notifications.

If you reinstall the application, it will start collecting and storing brand new data in the phone.

Where can I find the application's source code?

eRouška is published with open-source code. You can find it on GitHub (Android, iOS).

Frequent problems

Android: Basic recommendations for troubleshooting

If the app displays an error message please check that your operating system is updated (how to update Android) and that you are not using its beta version.

Then, please check whether there are new updates of eRouška in your store (Google Play (Android)).

We also recommend to enable automatic eRouška app updates. Steps for Android are: Open Google Play Store app, press My apps & games → choose the app to update → press three dots and select Enable auto update.

iOS: Basic recommendations for troubleshooting

If the app displays an error message please check that your operating system is updated (how to update iOS) and that you are not using its beta version.

Then, please check whether there are new updates of eRouška in your store (Apple App Store).

We also recommend to enable automatic eRouška app updates. Steps for iOS are: Go to Settings → [your name] → iTunes and App Store. Turn on App Updates.

Android: Cannot activate eRouška. Activation error 17 (Exposure Notification API is not available).

On Android devices, please follow these steps:

  1. Check if you are the primary user of the device, that Play Services are installed, and that Settings → Google → COVID-19 Exposure Notifications is available.
  2. Uninstall eRouška.
  3. Clear cache and data for Google Play Services and Play Store (see steps 2 and 3).
  4. Install eRouška and enable COVID-19 Exposure Notifications.

If you still experience issues with app activation, it is possible that your device does not support Bluetooth LE (Low Energy Advertising) or Bluetooth Multiple Advertisement, is not authorized for Exposure Notifications by Google, or does not have Exposure Notifications API.

iOS: Cannot activate eRouška (Error code: 3).

On iPhone devices, please follow these steps:

  1. Check for iOS updates. Check that you are not a beta tester.
  2. Uninstall eRouška.
  3. If Settings → Exposure Notifications are disabled, please press the toggle to enable them.
  4. Install eRouška and enable Exposure Notifications.

iOS: eRouška was paused on iPhone and cannot be resumed.

Only some iPhone users are affected by this after iOS update. Please try uninstall and reinstall eRouška. You will not lose any data from your iPhone because they are stored in the system.

iOS: What should I do if eRouška stops working after I recovered iPhone data from iCloud or got a new iPhone?

iOS 14.0 and 14.1 contain an error that disables the necessary Exposure Notifications settings after the phone data are recovered.

Please try one of the following steps:

  1. Go to Settings → Exposure Notifications → turn off Exposure Notifications. Open eRouška and confirm the required permissions.
  2. Uninstall eRouška, reinstall and activate it.
  3. Set our region as active: go to Settings → Exposure Notifications → No active region → Select our region from authorized regions → press Set as active region. Resume eRouška.

iOS: iPhone shows a notification that the exposure notifications location has changed.

Please turn off the toggle in Settings → Exposure Notifications → Availability Alerts.

iOS: On iPhone, eRouška displays error 401 or 500 when sending data.

Please uninstall eRouška and reinstall it from App Store. You will not lose your logged data because they are stored in your iPhone's system. If the SMS code expires when reinstalling, please contact us at, mention the error code, your full name and phone number. We will send you a new code.