Note: If you are running the stock Android ROM or another 3rd party ROM, visit the installation page. Installing Blandroid as an update may cause problems with your device and should be installed with the fastboot tool instead.
To manually check for available updates, press the menu button at the home screen, then "Settings", then "About phone", and then "System updates". If any new versions are available, you will see a notification and the option to download the update.
If your device does not have an available Internet connection, or a previous update application has failed, you can apply an update through your computer.
Visit the downloads page and download the latest upgrade version for your device.
If your device will not boot due to a previously failed update, boot into recovery mode using the key sequence specific to your device. Connect your device to your computer with its USB cable. At the recovery menu, choose "mounts and storage", then "mount USB storage". Drag the downloaded zip file to your device's mounted drive on your computer.
Otherwise, if your device is able to boot properly, connect your device to your computer with its USB cable. On your device, tap the "USB connected" notification and "Turn on USB storage". Drag the downloaded zip file to your device's mounted drive and then eject/unmount the drive.
Click "Turn off USB storage" on your device, then hold the power button, tap Reboot, then Recovery.
If you would like to backup your entire device first (always recommended), scroll down to "backup and restore", press the power button, and then select "Backup". Select "Go Back" to go back to the main Recovery menu. In the main Recovery menu, scroll down to "install zip from sdcard" with the volume down button, then press the power button, then select "choose zip from sdcard" and then select the zip file you just downloaded previously (which may be in a "downloads" directory). The update will be applied, and then you can select "reboot system now".