Yes, the conclusion of this report might be a little obvious to anyone who's been following the App Store closely, but it's true: Flurry's latest writeup of App Store stats suggests that keeping users playing a game or using an app can be a major factor in that app's success. Flurry filed the apps it follows into a set of four categories, based on star systems. Black Holes feature low amounts of monthly users, and low amounts of retention over a couple 30-day periods. Shooting Stars have put a lot of users together quickly, with high user numbers but relatively low retention. Red Dwarfs have lots of user retention, but low numbers overall -- these are cult favorites, used by a smaller amount of very loyal people. And