Looking at Jasper, it uses AT&T or Google or Facebook (wit.ai) as backend (forget the other two, offline speech recognition is hard because it's a data problem

Looking at Jasper, it uses AT&T or Google or Facebook (wit.ai) as backend (forget the other two, offline speech recognition is hard because it's a data problem and training your models is hard and your performance will be prohibitive). If you intent is privacy, then using the backends offered by AT&T or Google or FB doesn't fly.