‘These digital tools are not devoid of security flaws,’ government document says.
After the Tchap project based on Matrix, the French Prime Minister asks anyone in the gouvernement to use Olvid, the only app validated by the ANSSI, with metadata encryption and no centralised architecture nor contacts discovery. But only the front-ends are open source, not the back-end.
I downloaded and scanned it with App Manager. Google play billing, another Google something, and telemetry from someone else. Also has the Google maps api. Pass
Edit: I use SimpleX which has many of the same features (no phone number, ETEE, lots more) but is FOSS, has no trackers, has been audited by Trail of Bits, and can be self hosted if you wish. I am very happy with it after leaving Signal.
It's an Android app that can 'Scan for trackers and libraries in apps and list (all or only) tracking classes (and their code dump)' as well as many other functions