Hovering on the edge of awareness for most iOS users exists a class of apps that I hope you never have to use, or even see. I’m talking about assistive communication applications for the iPad and other tablets — used to help people unable to speak from injury, disease, or other reasons. One of the leaders of the pack (and the first to market a few years ago) is AssistiveWare’s Proloquo2Go, an application designed for easy customization for end-users to be given a voice, some for the first time in their lives….