I like everything by Toca Boca and they have several free apps to try. Many apps have video reviews that you can watch on YouTube so you can get an idea if they're right for you before downloading or purchasing. When my son was a little younger some of the apps I got for him were: Everything by Toca Boca, iWriteWords, Phone4Kids, (free) Neon Mania, My Play Home, Monster at the end of this Book, Charlie Brown Christmas (got it for .99 cents on Christmas day), The Electric Company, Doodle Dots .... The only app I've paid a significant amount of money for so far is Reading Rainbow ($30 for a 6 month subscription) which might be suited for a slightly older child .... but it is worth it! I periodically search for apps by PBS Kids, Sprout, Disney, Nickelodeon, Leap Frog, Fisher Price, Toca Boca, Dr. Seuss, anything he may have a specific interest in like Thomas the Train ... I'm probably forgetting a few ... but I often find good free or .99 cent apps that way! Some other apps I'm happy with but might be just a little advanced (not by much) at this time are EduKitty, Drawing Carl, Howl Mouse, Hungry Fish, Alien Buddies, Math Monsters.... I don't remember which ones were free.