"Sketcy" is great as far as I am concerned, but there is one major problem that the author should serously consider fixing.
When you watch a premade flip-book, the program unarchives it and when you are done it does not re-archive it; if you try to watch another, the program comes up with a blurb saying "ERROR not enough RAM" and you have to go into you memory and re-archive the one that you watched. This problem is not the end of the world - "Sketchy" is still a good program.
Note to anyone that makes a flip book - keep the size under 19k, because people with a lot of programs don't have the RAM to run any that are bigger.
Graphics - 10/10 as good as the calculator
Memory - 7/10 it's an app, and doesn't re-archive things
Usage - 10/10 very fun
Overall - 9/10