Toca Tea Party (US$1.99) offers an interactive party suitable for the very youngest iPad users. With bright colors and highly defined interaction opportunities, it works best for limited play, where users can "pour" tea, "eat" cake and listen to jazzy music.
This is not an app that will engage children who have reached kindergarten in the way that, for example, Cupcakeroo does. Its interaction is too simple: pour tea, serve cake, eat it. Preschoolers, however, should love it.
The design is charming and quite a lot of attention went into the details. Mopping up spilled tea, for example, is sure to be a hit. This is the board book equivalent for iOS apps -- so go in with that kind of expectation and you'll be pleased with what you find.