NxtApp 4 Kids, an educational math app, has updated with universal support for iPhone and iPad. The goal of the game is to complete number sequences by choosing which number comes next.
I'll admit, the misspelling of the world "next" in this app's name really bothers me, especially since it's an educational app targeted towards children; but putting that aside, NxtApp 4 Kids looks like a great app for learning about sequences.
[App Store link]
Details and screenshots after the break.