MY i phone 5C,When on a call my face seems to hit certain keys by a simple accidental touch (opens the contact list or sometimes mutes phone or turns on the speaker phone) never had this trouble with my i phone 4??? Please help..
There's a proximity sensor which detects when you put the phone up to your face. It's supposed to shut off the touch screen so that this doesn't happen. It sounds like yours isn't working properly. I'd first do a hard reset, just to be sure that it's not a software issue. Any chance your 5C is still under warranty? Apple Care Plus?