How do I get Windows 8.1 Update onto the Lumia 520, 620, 720, 525, 625, 820 or any other Windows 8 Phone?
I've updated my Lumia 520; it's easy. Just head to Settings and scroll down to System/Phone Update, then check for updates. Your phone will find it and prompt you to restart when it's ready to install.
Nice and easy!
check the availability