Here's how to upgrade the phone software to make sure the latest, most up-to-date version is running on your Nokia Lumia 820:
- From the Start screen, swipe to the left.
- Scroll down to and tap Settings.
- Scroll down to and tap phone update.
- Tap check for updates.
- Wait while the handset checks for available updates.
Click Next to continue.
If an update is available, follow the on-screen steps. Otherwise, your Nokia Lumia 820 has now checked for available updates.