I love this app; I use it all the time. Besides minor bug fixes, which you seem to be taking care of, I find the lack of social interaction a hindrance. A suggestion I have is maybe to add in a way to privately message someone, or make it so people can comment on others videos. It would make it much easier to collab with people and/or communicate in general. By the same token, I would then suggest adding in a block function if someone is misusing the features. This may just be my opinion, but I feel that, the easier it is to communicate, the more user-friendly the app will be.
Bella_Berg about Acapella from PicPlayPost