EFS Backup

An open source android app to backup and restore the EFS partition of any device.

EFS is a system partition in the root directory of the phone that contains very important and basic information about the device's identity like Wi-Fi MAC address, Bluetooth MAC address and the MOST IMPORTANT - IMEI address (nv_data.bin).

Now if this EFS partition accidentally gets corrupted or erased, the phone’s IMEI number will get erased and the device will become completely useless. It won't be able to make voice call further, as the carrier network will not recognize the phone. This can happen for a variety of reasons, including flashing a wrong or corrupted ROM. This kind of damage is not accepted by the service center. Only solution that the service center provides is to replace the motherboard of the device and that costs a lot of $$$!

Only a backup of the EFS partition can save the phone if something goes wrong with the EFS partition.


How to Use?

To backup:

  • Tap to open the app from the launcher
  • Grant root permissions
  • Check the device details that are shown within the app
  • Tap to backup the EFS partition (requires root permission)
  • 'efs*.img' backup img file will be created in the root directory of internal storage

To restore:

  • Tap to launch the app from the launcher
  • Grant root permissions
  • Tap Restore
  • Browse for the efs backup img file (only '.img' file will be valid)
  • Grant root permissions
  • Done

Necessary information and instructions are included in the app.

System Requirements

  • Android 4.0+ (Ice cream sandwich+)
  • Root permissions
  • Samsung device


Check the 'Releases' section in Github source.


Source code of the software can be found at my Github repository.


The source code is licensed under GNU General Public License v3 (GPL v3)

© 2014 Shubhang Rathore