Pros: Free, lots of images, good activity with kids
Cons: Hangs on low end devices, should have large screen to enjoy
Picturizr is a great mobile app for iPhone, iPad and Android. I personally prefer using my iPad with it because the large screen allows me to share the app with my younger brother (he has autism). Editing photos are easy because you just need to pinch to resize the graphics and just point and drag it anywhere on your screen to move it. It has also a bunch of free themes, overlays and frames you can downloading and easily delete to manage space. It also helps my brother identify certain objects i.e. I ask him if he wants to add "goofy eyes" or a "goofy nose" to the photo. I guess you can really get creative when using the app to teach kids body parts or how to maybe use the ipad.
I just emailed them at picturizr[at]isbx.com to get some free coupons (I got like $20) so I can try out paid themes and they turned out well. I tried using it on my HTC wildfire and it force closes sometimes so I don't know if its an issue with memory. I prefer using it on tablets so it becomes a good group activity. Sharing is also good with Facebook.