If I can offer any advice it is to focus on simple mechanics and keep production costs way down. Don't spend more than three months on launching your first title.
I'm wondering if indie teams should more or less do the same if they are not eyeing big hits, which few managed to pull off. Two months might be too stingy, but with the engine and tools built it might not be impossible to pull off a by quarter subscription?
The main creator of the 10mg collection was on the Eggplant Show recently and talked about releasing games quarterly and how unsustainable that is.
Every one game is quirky, vibrant and fun. For few of them I was disappointed that devs moved on instead of continuing working to bring out the potential, but after a while they would return to same concept and release a sequel.
Big studios solve this by publishing games by the hundreds.
You can be successful building mobile games, just like you can win the lottery. :)