Took my old 5 in because the screen had popped up out of the housing and I was not able to send or receive calls. He immediately knew it was my battery and showed me how he knew it was. (I later Googled this and learned that the 5's had an issue with exploding batteries and Apple had been replacing them. Thanks for the notification, Apple!) Took an hour to replace battery, recharge and clean the phone. I went to leave and realized that I still couldn't send or receive calls. He was quite puzzled, but had a few ideas about why it was happening. I left the phone with him and went back to my office. He called me later at work and asked if I recognized the number he was calling from. Yep, he had figured out the problem and fixed it. All of this cost me less than $100. He's a friendly, knowledgeable and helpful guy!