Ask HN: Where do you all go for state of the art ideas on growing mobile apps?

What's state of the art these days for growing a mobile app? Not building them, just the user retention and growth stuff.

Books seemed to have abandoned even addressing this concept like a decade ago :) I know there's the guy who sold the high school crush apps on Twitter whose 10gs a month for his private coaching thing. His name escapes me at the moment.

But what else are you all watching, reading, studying on the regular to grow a mobile app and keep people coming back to them.