Thanks for the code, I've been enjoying this - a rather quick reaction game to bin items by category (indoor/outdoor; color; shape; etc). The graphics really are nice, and there was obviously a lot of work that went into the user interface as it's quite polished.
The cactus was an unusual add requiring two fingers to get rid of it. I happened to be playing with a stylus (had it in my hand from doing something else) so it was a bit awkward ;-). Pretty neat twist, though, and I like it.
I also like the 3-category sessions, and the occasional time when two objects come out that need to both be sorted. More quick reaction thinking needed.
I'm not sure I'd ever use the IAP, but you earn coins with each play so not sure it'll really be needed. I do also like that the there are two game modes Classic & Fast, with the Fast one being over when you mess up, providing a quick fun game. There is another mode called "Yours" where it seems you can design your own rounds - sort of. They will pick the best for future publication in that mode. Nice idea and it'll be interesting to see how that pans out.