Corona-Warn-App: Tracing the Start of the Official COVID-19 Exposure Notification App for Germany
This provides insights into app adoption patterns for public health officials, but it is incremental as it focuses on initial deployment data without major methodological innovations.
The paper analyzed the early adoption of Germany's official COVID-19 contact tracing app, showing it generated nationwide traffic on launch day but local outbreaks did not lead to significant traffic increases.
On June 16, 2020, Germany launched an open-source smartphone contact tracing app ("Corona-Warn-App") to help tracing SARS-CoV-2 (coronavirus) infection chains. It uses a decentralized, privacy-preserving design based on the Exposure Notification APIs in which a centralized server is only used to distribute a list of keys of SARS-CoV-2 infected users that is fetched by the app once per day. Its success, however, depends on its adoption. In this poster, we characterize the early adoption of the app using Netflow traces captured directly at its hosting infrastructure. We show that the app generated traffic from allover Germany---already on the first day. We further observe that local COVID-19 outbreaks do not result in noticeable traffic increases.