Im not the first to point out that the study design has some issues, and in any case proving there isnt a difference is hard (this only shows that they failed to find a difference between drugs and dieting).
Still, judging by how many messaging apps are already out there today, Chorus.im seems to have the greatest chance of survival if it positions itself as a disposable, browser-based service for mobile devices a service you never download but visit when you need to.