Back in 2014 we made an iOS game* that got several million plays and some local press but never made enough money to motivate further work. I still like it and play it when killing time on flights. If you were solo and/or had very low living costs or expectations, or got a feature to kickstart things more, maybe you could make a modest living.

Doing it over, I think we'd probably put more time into making it a daily challenge or monetising differently or using a more neutral theme.

* https://hexiledgame.com/