Are there any good iPad games for kids to learn numbers? I'm looking for iPad games for my 4 year old daughter to learn numbers. I've tried many different games, like "Learn Numbers", "Counting101", "Animals Count", "Baby Phone", etc. but none of them are really good. They are either too simple, too hard or too boring.

I'm looking for something that is interactive, fun, and that my daughter can play by herself without asking me what the questions are (some games have questions written but not spoken out loud). She has learned all of the single digit numbers although sometimes she makes random mistakes with them. She doesn't know about two-digit numbers except 10, 11 and 12. If there is a game with princesses it would be perfect for her :)

Could someone here please let me know, what is a good game to try out? If possible, please describe why you think it's good.

Many thanks.

EDIT: I got the first answer for this question after my daughter has mastered numbers until 20. I think it's good for her right now. I don't try push her much at this age. So I accept Numberland since it's the first answer although it seems to be too simple at the first glance. I didn't try other apps yet but will give them a try later. Thank you all for your effort.
You can try Numberland (App Store). It's available in 3 languages: English, French and Spanish. It won a Parents' Choice award in Fall 2011.

Check out the video demo.