Not to sure if people have already given this a shot but I'd thought I'd share.
I have iSSH on my my iPad which can do X.
Using this I've been able to get Scratch up and running on the iPad. It's not perfect but as a proof of concept it does work. Also it might be of use if you want to introduce a smaller child to the RPi you can do it sitting on the sofa rather than setting up the TV which pushes everything away.