Disabled Communication App Development

I have an idea to develop a basic communication app that would assist both carers and anyone that struggles to talk or communicate.

 I have an idea to develop a basic communication app that would assist both carers and anyone that struggles to talk or communicate, In my grandfathers case this is because of a stroke which left him barely able to move and unable to talk. I have no doubt that this project would work and briefly studied IT at college so know what im in for so would like to see it out there helping people asap. I do plan on a very small charge for buying the app as ongoing I hope to continue developing the app to a far more advanced stage after the initial and basic release. I would like to develop this first for apple and then android and google play however I am lacking the funds, equipment and software to do so. Please help.