This app was mentioned in 3 comments, with an average of 1.00 upvote
Line camera is fun because it lets you put all sorts of stickers and cute things on your photos.
The standard Words With Friends and Draw Something are good too since you guys can play it together. Both are good because she can be creative :) FarmVille2, Plants VS Zombies, and Minecraft are some of my favourite games.
I'm a fan of LINE Camera for things like filters, stickers, and frames.
Dunno about the "say cheese" though.
Samsung default camera app has both though, but don't know if it will work on other phones.