A student I work with developed this app for iOS, called Swamp Mess.  It’s a simple memory game, but fun to play.  My 2 year old son LOVES it.  And the background “music” is bullfrogs, so its much less annoying than other games he plays… 🙂

https://itunes.apple.com/us/app/swamp-mess/id1082174609?ls=1&mt=8