I am running an APPLE XR with iOS 12.3 & have no sound. I’d really suggest taking a couple of steps back on these app projects. You’ve spent a bunch of time setting these guys up, spiffing their look, etc., & visually it’s all pretty good (although I’d personallyalways stick with the industry standard font choices: NEW TIMES ROMAN or COURIER, & never deviate).
But it seems to me that given the time already spent on the concepts, you’d be ahead of the game if you relaunched once the wrinkles were starched out, or perhaps triple focusing on one concept, rather than scattering energy at very different offerings. Just a thought is all.