My nearly 13 year old DS is keen to have this App. I am not going to let him, but I am not sure why?
Whatsapp has disappearing messages, people could potentially upload inappropriate photos/videos, someone's, friend's uncle could get hold of their number etc so what's the difference?
Also if anyone has any great reasons I could fire back at him tonight that would be great! 
He has watched the Social Dilemma with me and he did take an interest. It has made him understand why it is important to come off his phone.