This is an older article I recently read. It has some good apps for autism.
http://www.eschoolnews.com/2013/06/14/27-visual-sensory-and-augmentative-apps-for-autism/?ast=105&astc=10088
http://www.eschoolnews.com/2013/06/14/27-visual-sensory-and-augmentative-apps-for-autism/?ast=105&astc=10088