If you’re still using a Nexus 4, Google appears to finally be updating the device to the latest version of Android. The 5.1 Lollipop update is rolling out OTA, although the factory image is still MIA.
Fortunately, installing the OTA file on your device isn’t too hard, and we’ve got a solid guide to get you up and running if you don’t want to wait for the update to hit your device.
If you don’t mind being a little patient, though, the notification should hit your device pretty soon.
source: Nexus 4 Android 5.1 OTA