aa: free game app for iphone, ipad

My students recently urged me to give 'aa' a try. No, I am not an alcoholic!  'Aa' is the name of a 'test your reflexes' game.  Look at the image.  The big wheel is turning, sometimes at a constant rate, sometimes at a variable rate.
When there is room, you must shoot the next number so that it does not crash into a spoke.
The Good: 'aa' is fast, fun and very addictive.
The Bad: The game doesn't vary much. Sometimes the wheel will spin clockwise, sometimes counter clockwise. That's basically it.
The Ugly: multiple times, I was very patient, waiting for the wheel to spin and shoot into a gap.....when suddenly, the program thinks that  there's been a collision. This has happened maybe 10 times to me so far.
The miscellaneous: I was stuck on level 26 for at least an hour.  Now I'm stuck on level 49 and I don't think I'll get past it.  Would you believe that there are 525 'entirely unique' levels? Once you've done 48 levels, that's enough.  If you want to play a genuine variation, look for their other apps: ff, au, rr and uu.
https://itunes.apple.com/au/app/aa/id905852173?mt=8