The problem that I have with Obsidian in android is that you can only have a single vault open at time. But there is a 'way' to make it more easy to work with it. Created two shortcuts using a 3rd party application and you can open without having to manually switch vaults.
https://play.google.com/store/apps/details?id=rk.android.app.shortcutmaker
I'm using this app, but unfortunately seems it's not open source.
Sharing to Obsidian still an issues because it will share to the last opened vault. Need to find a better way to do it.