Gallaudet's Visual Language and Visual Learning (VL2) storybooks in app form. Stories are told in ASL and English. Built on bilingual learning principles.
The National Leadership Consortium on Developmental Disabilities at the University of Delaware has a nice list of biographical and autobiographical texts and movie documentaries.
Bookr is a free writing tool. You can easily insert pictures from Flickr, add pages to make longer book. User-friendly. No supports for kids with disabilities, but one more place for parent-child or teacher-child co-construction and conversation. Can't beat the price.