Any good iphone apps for 3/4 year olds?

[Teachermumof3]

DD2 loves playing on my phone whilst waiting for things-doctor/hospital appointments etc, but I was wondering if there were any other good apps she might like?

We already have-Monkey Lunchbox, Toy story book+matching game, Peppa Pig, Humf.

She likes Disney films, but I'm not sure if there are any god Disney aps?

There are a few good apps by duck duck moose, wheels on the bus and incy wincy spider etc. Monster matching is good too.

You Tube kept my godson amused for an hour and a bit last time they were here (stuck in station waiting for train) Loads of cbeebies episodes on there.

My 4 year old loves Angry Birds. She can be transfixed by it for an hour :0
Which is about as long as the iPhone battery lasts before carking!