iPhone Wifi not working? Reset your network settings | A Mountain Top, LLC.
From the Home Screen, I clicked on "Settings". From there, I scrolled down to "General" and clicked on it. From there, I scrolled to the bottom, clicked "Reset", then "Reset Network Settings". After accepting the warning that I was doing something dangerous and clicking the giant red button, the iPhone started buzzing and shaking and generally throwing a fit. After it was done getting reset, I simply went back into Settings -> Wifi, saw my network, connected and it worked!