Google developers website. So those who did not get the OTA yet or encountered some issues while trying to flash, your alternative is ready for you.
As with the OTA update, you will need to have the Android SDK installed before attempting to go to KitKat wonderland. The SDK is needed because it contains the latest version of adb and fastboot needed for flashing.
You also need a MicroUSB cable in order to execute adb sideload, fastboot flash and others. You’ll need to have the bootloader unlocked as well, but note that this command will wipe out your data.
Now to complete the transition you’ll have to follow three steps.
1. Download the factory image (includes full system, bootloader, recovery, kernel (boot.img) and radio (not available for Wi-Fi only variants) according to your model.
2. Unpack the tgz archive
3. Reboot into the bootloader and run the flash-all script
Android 4.4 KitKat was announced back in September and made it out into the world last month.
The update brings numerous tweaks and improvements like the new revamped hangouts app which integrates SMS with Chat, better cloud storage integration, system wide wireless printing or new lock screen that shows additional data.
Users will also be able to open and save document files on Google Drive, other cloud storage or directly onto their slates.
Google announced this Halloween that the factory images and the binaries for the Nexus 7 2013, Nexus 7 2012 and Nexus 10 will be made available after the OTAs popped up and the search giant kept true to its word.
Download Nexus 7 and Nexus 10 Android 4.4 KitKat Factory Images
The update has been made available for the Google Nexus 4, as well
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