The number of active users of the SwissCovid app has risen since reaching a nadir nearly two weeks ago.
On 25 June 2020, Switzerland’s contact tracing app, known as SwissCovid, became available for download. Over the following 10 days, around 1.6 million people downloaded the app. However, not everyone downloading it switched it on.
On 8 July 2020, the app had 1,017,504 active users. But by 11 July, this number had fallen to 959,815, according to Switzerland’s Federal Statistical Office. Since then the number of active users has risen, reaching 1,160,000 by 23 July 2020. 1,160,000 represents around 16% of Switzerland’s adult population.
To make the system effective, some argue that 60% of the population would need to use it. However, others disagree. Modelling done at Oxford University suggests that the effectiveness of tracing apps isn’t binary. Their model shows that even 10% app penetration would have an impact.
The SwissCovid app, developed by a team at EPFL, is the first in Europe to use Google and Apple application programming interfaces (API), allowing devices using Android and iOS operating systems to work together. The app uses Bluetooth Low Energy technology and encryption to record contact between smartphones that are within at least 1.5 metres of each other for a period of at least 15 minutes.
If someone using the app tests positive, they can request a code, known as a covid code. Upon entry, data from the infected person’s phone is shared with a central server, which then sends messages to all those using the app that were in close contact with the person. These people can then test and isolate. The video below shows how it works.
429 covid codes were entered across the week ending to 22 July 2020.