Show number of contacts

[zukunft]

To be transparent to the user the number of Bluetooth contacts registered should be shown to the user. At the moment the app just shows "tracing aktiv".

[zukunft]

A build from the develop branch now shows the number of handshakes on the debug page, but it takes a while, until the screen is updated. Maybe display the time of the last handshake and the time of the last update. Maybe the delay is due to the missing synchronization with the server.

[Phlogi]

How would one enable the debugging mode and check this? Is a debug build required?

[zukunft]

@Phlogi I guess, in the final version, the debug page will be removed, but at the moment it is shown when you do the normal build of the develop branch. In a previous version of the next-step app the number of handshakes have been shown directly on the main page, which I think, is better. I would even suggest, that it should be differentiated between handshakes with Bluetooth devices with app and Bluetooth devices without tracing app. At the moment it looks like all Bluetooth handshakes are counted.

[Phlogi]

If the app is showing any counter it should only be "real" contacts with others having the app too. As you describe it, would this include all Bluetooth handshakes e.g. car radio, headphones etc.? I hope not :)

[zukunft]

The actual version is a test version and it looks to me, that it includes also handshakes to phones, that does not have the app running, because I got over 50 handshakes in one day and I guess not everybody has the app at the moment. That's why showing the number if real contacts is also good for testing.

[koehleru]

@Phlogi @zukunft i think it is not possible to show "real" contacts because of the design of the tracing functionality. For privacy protection every App generates every 15 minutes a new ID which transmitted via bluetooth. if you have two devices, every 15 minutes you have a new "contact" without changing the the device in your neighbourhood. The app does not know whether it is a new "real" contact or just a new id

[zukunft]

OK, got it. Maybe this should be written on the UI screen to reduce confusion. I guess to show the number of contacts on the main app UI could be helpful to have some kind of "app is working properly" indicator.
Even if it is not possible to show the "real" contacts, would it be possible to exclude contacts with Bluetooth devices that does not have a DT-3T compatible app? Maybe a kind of checksum can be included in the ID.

[zukunft]

This looks to me similar to SwissCovid/swisscovid-ux-screenflows#3

[naomi-albert]

Is there a way to see the ID's of the devices my app has been in contact with?