@robin that's one of the core features! We only allow apps that are fully open source (i.e. no proprietary components), so we can build them from the source and you (the users) know "what's inside". This also means everone can review the code and deduce from that to the APK. And a potential security audit would also tell how secure the app you install is. No trackers in the code = no trackers in the app, etc.pp.