So many apps...so little time.  There are several great visual timers that can also be used as a scheduler:   Vis Timer, EZbuzz and my favorite, Alarmed
Have the student put in various times for daily activities and the app will 'remind' them visually and/or auditorily what is next.

Re-Enabled

iOS’s impact on those with impairments isn’t just a marketing slide; it’s profound.

Re-Enabled By Steven Aquino

Click above to read a great article about a paraprofessional who is visually impaired and his use of iPad's  accessibility features and how he uses iPads with cognitively disabled and autistic students in the classroom.