Originally Posted by MrBottomTooth

I was having issues with my WiFi after mine updated. I cleared the cache on mine and seems to have fixed it.

Power off phone.
hold volume up and home buttons down, then press and hold power at the same time.
When the phone vibrates release only the power button.
this will boot into a special menu that lets you wipe the cache partition. Use volume buttons to navigate the menu and the power button to select.