What's so special about this application that a concerted week of coding could not duplicate? It seems like a list of icons, and when you touch an icon a word is spoken. There is a facility to add new icons. The application also seems to permanently fix the location of each "learned" icon, so that as the child grows their vocabulary consists of an expanding set of "muscle memory" movements. There is also a facility to flag attempts to add duplicate icons. [1]
Have I missed something here?
[1] http://www.speakforyourself.org/About_The_App.html
Edit: Some interesting links:
Open Source Assistive Technology Software: http://www.oatsoft.org/
A collection of 5000 pictograms, necessary for an AAC application, licensed under CC-BY-NC-SA: http://www.oatsoft.org/Software/arasaac-pictograms/
Edit:
pVoice, open source Augmentative and Alternative Communication: http://www.oatsoft.org/Software/pvoice