hello. i just want to understand why this happens. so a have facebook messenger and whatsapp installed on my iphone 5s. heres the problem, i can only receive facebook calls when the app is open or running in the background, when using whatsapp i can have the app closed on the multitask and i can receive a call with no problem. i have tried enabling background app refresh and still this continuous. is this normal? why would facebook messenger have a call feature if to only works when the app is running? and why does whatsapp witch is owned by facebook doesn't have the same issue?
sorry for the bad english.
sorry for the bad english.