Was waiting on someone to chime in with this. I agree. I'm looking for a backup on Android. I'm not harboring delusions about there being a real contender at this point.
I tried @Yana a while ago, it was ok but not comparable. When @freerse has amber support this would be an option. For now I go without backup client
https://openvibe.social/ is amazing on Android but no Amber login support yet too.