Free tools to protect root during the update, the OTA manufacturer As well as unroot temporary use. The program is free  and has the source code open Download link:  http://dl.project-voodoo.org/apps/VoodooOTARootKeeper.apk This app is a backup or a backup protected from the root device Your are If different conditions together matching data are OTA RootKeeper makes up the root from OTA, healthy out System required: System partition  Ext2, Ext3, or Ext4 Upgrade, system partition, the full format and rewrite does not This program on the system, The following quite effective: - Nexus S - Galaxy Nexus - Every Honeycomb tablet Systems that protect the program, they doesn't work: - HTC Desire - Samsung Galaxy Spica - Samsung Galaxy S / SII