Android has many secret codes that can be accessed using the Android phone app (dialler). These secret codes can do many things such as allowing you to test your device GPS and LCD display among others. If you want to learn more about what secret codes are available on your device, then you can search for them on Google. The list is too long for this post.
For the benefit of this post, I’d like to point my readers to a useful secret code that can emergency factory reset your Android device. You may have or are currently experiencing problems resetting your device.
If you have a Nexus 5 go to Settings > Backup & reset > Factory data reset, sometimes this function fails for whatever reason. One use I have for factory reset is when you want to sell your device. Remember it’s not 100% guaranteed that all data will be erased, as forensics examination could determine data remnants and allow an investigator to exfiltrate your personal data.
The chances of this happening are low but would be much higher if you are hiding something unsavory on your device that might be of interest to the Police or government agencies.
If you are 100% sure you want to factory reset your Android device (this is applicable to all Android devices) please be aware the following does not ask you for confirmation:
- Open your Android phone app (dialler)
- Type *2767*3855# (you will receive no confirmation prompt – BEWARE!)
- Your device will shut down, restart, and be completely wiped (see footnote)
- Android OS version and native apps remain intact
My favorite approach for securely erasing an Android device is to use Android OS encryption. You can set up encryption before or after you start using your device. I’d suggest you do this before you start using your device.
If you have a Nexus 5 (if you have another Android device you can also do this) you should go to Settings > Security > Encrypt phone. You will need a numeric PIN or password to decrypt your phone each time you power it on.
The above will encrypt your accounts, settings, downloaded apps, and their data, media, and other files. You cannot decrypt your phone except by performing a factory data reset which will erase all your data. This would be my recommended approach for erasing data securely on your Android device.