Corona-Warn-App is the official and open-source
COVID-19 contact tracing app used for
digital contact tracing
Digital contact tracing is a method of contact tracing relying on tracking systems, most often based on mobile devices, to determine contact between an infected patient and a user. It came to public prominence in the form of COVID-19 apps during ...
in Germany made by
SAP
Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant.
Sap is distinct from latex, resin, or cell sap; it is a separ ...
and
Deutsche Telekom subsidiary
T-Systems
T-Systems International GmbH (T-Systems) is an internationally operating service provider for information technologies and digital transformation. The company is part of Deutsche Telekom AG and is headquartered in Frankfurt am Main.
As of 2012, T ...
.
It had been downloaded 22.8 million times as of 19 November 2020 and 26.2 million times as of 18 March 2021.
The app has been promoted by billboard and broadcast advertisements, e.g. in cooperation with the
German Football Association (DFB) and other prominent companies.
The German government has announced that the app would no longer exchange tracing information as of April 30, 2023 & would enter hibernation as of June 1, 2023.
Effectiveness
Experts believe that time saved by using the app can be critical for improving the effectiveness
contact tracing
In public health, contact tracing is the process of identifying persons who may have been exposed to an infected person ("contacts") and subsequent collection of further data to assess transmission. By tracing the contacts of infected individua ...
efforts.
Some
virologists say when at least 60% of people in Germany use it, it would be very effective.
Functioning
The app works with the
Exposure Notification
The (Google/Apple) Exposure Notification (GAEN) system, originally known as the Privacy-Preserving Contact Tracing Project, is a framework and protocol specification developed by Apple Inc. and Google to facilitate digital contact tracing during ...
Framework (what is implemented in Google Play Services for Android and in iOS) by using
Bluetooth
Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is limi ...
to exchange codes with app users that are within 1.5 meters of each other for a period of at least 10 minutes.
Anyone who tests positive for COVID-19 can share this information voluntarily with the app. Other app users are then notified about when, how long and at what distance they had contact with the infected person within a 14-day period. Testing is available for persons on a voluntary basis.
Server architecture
Based on the
Client–server model
The client–server model is a distributed application structure that partitions tasks or workloads between the providers of a resource or service, called servers, and service requesters, called clients. Often clients and servers communicate ove ...
five servers are operated within the app backend:
* the Corona-Warn-App server. It saves the authorized keys of infected users, called diagnosis keys, of the last 14 days in its database. Stored diagnosis keys are concentrated in regularly changed blocks which are sent to the Content Delivery Network. This interface provides the keys for the app clients to download and locally calculate a potential exposure risk.
* the Verification server. It is responsible for documenting the approval of the user to share their positive test result with the app and also to verify the test result.
* the Portal Server. It generates a so-called teleTAN token if the user didn't give their consent to share their test result with the app at first but then changed their mind or if the local public health authority or test laboratory isn't connected to the app system yet.
* the Test Result Server. It saves the test results provided by the local public health authorities or test laboratories for further use within the backend.
* the Federation Gateway Server. It connects to the national Corona-Warn-App servers of participating EU countries to enable transnational key exchange.
By the distribution of the data on different servers the decoupling of the data becomes possible and results in an obstructed
tracing of the app users.
Report of a positive COVID-19 test
The app provides a function to warn other app users by uploading their positive test result on a voluntarily and anonymous basis to the Corona-Warn-App server.
In case the local public health authority or test laboratory is already connected to the app system, the user receives a
QR-Code when the swab specimen is taken that can be scanned in the app. After scanning the QR-Code und the user getting authorized by the Verification server, the app receives an individual Registration token which gets stored locally and with which the status and the result of the test can be checked manually as well as automatically.
If the local public health authority or test laboratory isn't connected to the app system yet and the user wants to share their positive test result with other app users, it is required to request a teleTAN token by calling the verification hotline of the app.
In both cases, the user can upload their diagnosis keys of the last 14 days to the Corona-Warn-App server in case their consent to share the information is given. The Corona-Warn-App server then verifies the uploaded keys by asking the Verification server if the keys are valid and if they are, the Corona-Warn-App server stores them in its database.
Privacy
The use of the app is voluntary. The app implements
decentralized data storage to ensure
data privacy
Information privacy is the relationship between the collection and dissemination of data, technology, the public expectation of privacy, contextual information norms, and the legal and political issues surrounding them. It is also known as data pr ...
.
Employers can require that Corona-Warn be installed on company phones, but can not compel its use on private phones.
Funding
The
open source app, which costs €20 million to develop is intended to supplement human
contact tracing
In public health, contact tracing is the process of identifying persons who may have been exposed to an infected person ("contacts") and subsequent collection of further data to assess transmission. By tracing the contacts of infected individua ...
efforts, which Germany put in place during the early stages of the
COVID-19 pandemic in Germany
The COVID-19 pandemic in Germany has resulted in confirmed cases of COVID-19 and deaths.
On 27 January 2020, the first case in Germany was confirmed near Munich, Bavaria. By mid February, the arising cluster of cases had been fully containe ...
. In August 2022, a spokesperson for the German ministry of health announced that the total costs including all additional developments are now estimated to be closer to €150m.
Interoperability
At its start the app only worked in Germany, and
Jens Spahn
Jens Georg Spahn (born 16 May 1980) is a German politician who served as Federal Minister of Health in the fourth cabinet of Chancellor Angela Merkel from 2018 to 2021. A member of the centre-right Christian Democratic Union (CDU), he has bee ...
, than
Federal Minister of Health (CDU), has said the development of a Europe-wide system is a future goal.
[ With the update published on 19 October 2020 the app supports key-exchanges with the ''EU Interoperability Gateway'' and is therefore able to communicate with contact tracing apps from Ireland and ]Italy
Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...
. Austria
Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...
, Belgium, Czech Republic
The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...
, Croatia, Cyprus
Cyprus ; tr, Kıbrıs (), officially the Republic of Cyprus,, , lit: Republic of Cyprus is an island country located south of the Anatolian Peninsula in the eastern Mediterranean Sea. Its continental position is disputed; while it is ge ...
, Denmark, Finland
Finland ( fi, Suomi ; sv, Finland ), officially the Republic of Finland (; ), is a Nordic country in Northern Europe. It shares land borders with Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of B ...
, Ireland, Italy, Latvia, Malta, Netherlands, Norway, Poland, Slovenia
Slovenia ( ; sl, Slovenija ), officially the Republic of Slovenia (Slovene: , abbr.: ''RS''), is a country in Central Europe. It is bordered by Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the southeast, an ...
, Spain and Switzerland had joined the gateway as well and are also able to exchange keys with ''Corona-Warn-App''.
The app can be downloaded in many App stores outside of Germany. However, as of August 2021, the app is still unavailable for those of notable national German minorities like Turks
Turk or Turks may refer to:
Communities and ethnic groups
* Turkic peoples, a collection of ethnic groups who speak Turkic languages
* Turkish people, or the Turks, a Turkic ethnic group and nation
* Turkish citizen, a citizen of the Republic ...
, Russians
, native_name_lang = ru
, image =
, caption =
, population =
, popplace =
118 million Russians in the Russian Federation (2002 '' Winkler Prins'' estimate)
, region1 =
, pop1 ...
or Ukrainians
Ukrainians ( uk, Українці, Ukraintsi, ) are an East Slavic ethnic group native to Ukraine. They are the seventh-largest nation in Europe. The native language of the Ukrainians is Ukrainian. The majority of Ukrainians are Eastern Ort ...
, who use App stores of their home countries.
Software variants
An unofficial Corona-Warn-App has been released on F-Droid
F-Droid is an app store and software repository for Android, serving a similar function to the Google Play store. The main repository, hosted by the project, contains only free and open source apps. Applications can be browsed, downloaded and ...
, making the app available without proprietary components on Android phones.
Literature
* Thomas Köllmann: Die Corona-Warn-App – Schnittstelle zwischen Datenschutz- und Arbeitsrecht. In: Neue Zeitschrift für Arbeitsrecht. Nr. 13, 10. Juli 2020, S. 831–836.
References
External links
Official website
Official website
Corona-Warn-App
on the website of the Bundesregierung {{in lang, de
Application software
COVID-19 contact tracing apps
COVID-19 pandemic in Germany