How to retain root access after Over-the-air OTA update? Well, you can do so with the help of Voodoo OTA Root Keeper. Voodoo OTA Root Keeper also serves as temporary un-root tool. It makes a backup or a protected backup of your device root. Sound great for a free solution, right? However, it works with conditions ~ /system partition as Ext2, Ext3 or Ext4 and upgrades not formatting or overwriting completely the whole partition. Known working devices are Google Nexus S and all the Honeycomb tablets. And not working on Samsung Galaxy series. Note – root access is required.