When I first got this phone I was able to use web-based apps while I was on a call. For instance I have Waze which uses GPS to track the traffic in my area and that used to tell me about traffic if I was on a call. Also, I used to be able to use iMessage while I was on a call even when I wasn't connected to wifi. Now if I'm on a call, all of my imessages turn to texts and I cannot do anything internet based. Why?