So IOS 11 has completely crippled my iphone 5S. Everything has slowed to a crawl. The phone lags constantly. The screen freezes for long periods of time. The phone completely reboots often. Apps crash, the phone crashes, everything is now completely miserable. Not to mention that less than 24 hours after updating, my battery swelled up and had to be immediately replaced. I should say the phone was working 100% perfectly well before the update.