Updating image android
Your downloading of the system image and use of the device software may also be subject to certain third-party terms of service, which can be found in Settings environment variable or change into the directory containing the executable.Also be certain that you've set up USB access for your device, as described in Run Apps on a Hardware Device.
This will ensure that you don’t lose any data in case something goes wrong during the update process.
Since those devices were specifically released in order to showcase Google’s unaltered version of Android, your Nexus smartphone should prompt you to upgrade your software whenever a new version is released.
Another exception are any low-end devices branded with Google’s Android One platform.
Refer to this Android developer page to determine which version of Android your device is running.
For example, 4.0.4 corresponds to Ice Cream Sandwich, a version of Android that was released in 2012.