I used to use gobandroid off f-droid, but these days I use crazystone: I like its ai for casual play (and I usually only play casual!). It does seem to have a deep love for talking home with no explanation when it starts up though, so on Lineage I just disable its internet permission.

Online-go is good but I haven’t really gotten into playing against strangers on the internet: I feel I should take it more seriously when I’m against a real person!

Wish I had people offline to play with sometimes though.