Apparently, the developers are ignoring the reviews. I just purchased the Crescendo and the Tenuto. MysteryVibe works fine for the Tenuto. For the Crescendo, not so much. When I first turned it on, MysteryVibe updates the firmware. After it finished, MysteryVibe finds the Crescendo and then the blue tooth connection immediately fails. Very disappointing, especially since it apparently hasn’t worked for awhile—one of the complaints about this was from 2018. Since it is now 2020, you would think the developer would have fixed it.