The "decentralized" app was first announced on Monday, and it's now available to "several thousand" Swiss citizens. Contact tracing apps, for the unaware, function by allowing users to determine when they've been in close contact with a confirmed Covid-19 carrier.
With SwissCovid in particular, If such a situation arises, app users will receive a notification informing them of the time and date of contact, as well as a set of instructions to follow moving forward (to help them get tested). For such a notification to pop up on your device, you must have been within two meters of an infected individual for longer than 15 minutes. If enough people download the app and actively use it, Covid-19's spread could theoretically be tracked and contained.
Obviously, privacy is a major concern with apps like SwissCovid, and that's something its developers are well aware of. The app was designed to minimize the "collection and sharing" of user data, and its decentralized nature means all "essential" operations are carried out on each user's device, not on a remote server.
However, if a user does later test positive for Covid-19, Swiss college EFPL (the institution behind this app) says the individual can voluntarily share where they were during the days that they might have been contagious. These details are handed off to a Swiss server upon inputting a single-use code (given to a Covid-19 carrier by their doctor) into the app.
SwissCovid will be in an early pilot phase for a few weeks, while Swiss parliament "decides on the revision of the law on epidemics," which could directly impact how the app will function down the line. For now, SwissCovid will only be available to a handful of "pilot populations," including workers at the EPFL itself, members of the Swiss Army, and government employees.
Image credit: Zigres