I don't think there is a single one. The stock app is quite good but has various bugs e.g. disregards the configured storage location when you want to shoot RAW (which needs the Pro mode). Also the Pro mode is not saved when you exit the app. I have tried all the others I could find and none of them works fully. I would like a better quality app because the stock one produces oversharpened and oversaturated pics. I know a lot of people like that sort of thing but one gets bored with it after a while.