https://www.b4x.com/android/forum/threads/b4x-supabase-the-open-source-firebase-alternative.149855/
Share state between users with Realtime Presence.
https://supabase.com/docs/guides/realtime/presence
Setup
https://www.b4x.com/android/forum/threads/b4x-supabase-realtime.156354/
Sync and track...