For iOS
- Plug your device into power and connect to Wi-Fi.
- Go to Settings > General, then tap Software Update.
- Tap Install Now.
For Android
- Make sure your device is connected to Wi-Fi.
- Open Settings.
- Select About Phone.
- Tap Check for Updates.
- If an update is available, an Update button will appear. Tap it.
- Install. Your phone will reboot.