I don't expect an official app. There are some 3rd party ones.
Our frontend is a PWA which integrates very well into Android.
Actionable push notifications can be achieved with the notify.HTML5 platform[1]. Nice writeup what you can achieve here[2].
The only thing that cannot be achieved with the PWA is sending location updates for presence detection. But that can easily be achieved with OwnTracks [3] sending updates over HTTP.
