Apparently, I’m not the only person who thought OnlyMove was a good name for a board-game training project :D

I recently discovered onlymove.net, a Go training app built by another solo developer.

I primarily play chess, but there were a couple of years when I switched almost completely to Go and even reached 1 kyu on Fox. That was quite a while ago, though, and I haven’t played seriously since.

So I gave it a try.

It gives you Go problems on 9×9 and 13×13 boards, with difficulty adjusted to your level. I managed to reach 10 kyu, which felt nice, although I suspect my real Fox rank would be considerably worse today.

The interesting part came when the app identified ko as one of my weaknesses and started giving me more ko problems.

OnlyMove.net showing a 9×9 Go problem beside highlighted feedback: “You are weak at ko” and “You undervalue territory”. — OnlyMove.net flags ko and undervaluing territory as weaknesses.

I wasn’t particularly happy about that. My rating had been growing quite nicely until then :)

But that’s also what I liked about the app. It doesn’t just give you problems you’re comfortable with. It tries to find what you need to work on.

I contacted the developer afterward, and we had a nice conversation about how the training works. Turns out OnlyMove.net is also a solo side project, just like OnlyMove.ai.

So, two independent projects, the same name, and two developers who would rather build things than market them.

If you play Go or want to give it a try, check out OnlyMove.net.

I enjoyed it. Even the ko problems.

What Makes OnlyMove.net Interesting

A few things that stand out to me:

Whole-board problems. Not just life and death. You need to consider the entire position, including ko, endgame, and moves elsewhere on the board.
Adaptive difficulty. The app estimates your level and aims to give you problems you’ll solve about 80% of the time.
Personalized training. It identifies areas where you’re weaker and gives you more opportunities to practice them.
Spaced repetition. Problems you fail return later, sometimes rotated or mirrored, so you have to read the position again.
A huge problem collection. Over 220,000 positions generated and verified with KataGo.

And it’s completely free.