I built 2 games, 200K downloads. I didn't quit to work on that particularly but it took me only 3 weeks to build a very simple react native trivia game that I knew instantly it was going to be a hit. The game is only for a specific european country, so, for the total population, it was pretty cool. It was top charts on app store / play store for a while and the hundreds of reviews of people loving the game changed my life.

I eventually needed to take a job since it wasn't profitable for long (2-3 months) and my plan now is to build other games and quit the boring corporate job once for all.

The only advice I have: launch as early as you can. On my second game I waited unnecessary months, and I realized I could've prioritize a lot better.