Has worked fine for me. That said, I did have the video camera freeze on me about 10 seconds in to a video. Really upsetting because I was recording my daughter play music and missed most of it. I hate iOS 8.
The success of mine is hit or miss. I have tried rebooting, hard reset, etc. I am running iOS 8.0. This is my second replacement phone, and it has been this way for me on each one. Not sure the reason.
Yes I have issues sometimes. The little icon is tucked too far in the right corner and the touch area to activate it is too small. For a screen so large it needs to be bigger or not nearly completely up against the bezel like it is now.