Cerberus is an android application that helps you to get your phone back if it has been lost or stolen. It allows your phone's location to be tracked via the Cerberus website, or by SMS messages. In addition Cerberus allows you to take a picture or video of the suspected thief and even listen to what they are saying. Cerberus has a one time cost of £2.59 for up to 5 devices.
Software like Cerberus is great if you lose your phone, however if it is stolen it is very likely that the thief will immediately turn the device off, wipe it and then sell it on at a later date. Wiping the device effectively removes the anti theft software, leaving you with no clues as to where your device is. A way around this problem is to include the anti theft software as part of the phones ROM. This way even after a hard reset you can still track your phone's location.
Cerberus includes a special install file that allow you to integrate it into your rom. In order to do this you must have an unlocked bootloader. XDA developers have a huge amount of information regarding rooting, unlocking and installing custom roms on your android device. I have a UK GSM Samsung Galaxy Nexus and followed these instructions to root the device and return it to stock condition.
Go to the Cerberus website and download the cerberus_disguised-ICS.zip file. Copy the zip file over to your android device.
Follow steps 1 and 2 of these instructions. This downloads a recovery image file that will allow us to install the Cerberus application from a zip file.
If you don't have the fastboot application then you can download it from this post where it named platform_tools-V??.zip. Before running fastboot make sure you have correctly installed the drivers for your device, see this post for more details.
Plug your Nexus into your computer and switch it off. Start your Nexus in bootloader mode by holding power, volume up and volume down at the same time.
On the computer open up a command prompt and type "fastboot devices". This should show the device ID of your phone. If not then the phones drivers are not correctly installed on your PC.
Use the volume keys to move up and down, and the power button to select.
Select "install zip from sdcard"
Select "choose zip from sdcard"
Restart the phone.
Since Cerberus is hidden from the application tray you must dial a phone number to access it.
The default is 23723787.
Login with your Cerberus username and password and configure the application as desired.
Go to https://www.cerberusapp.com to check that your device shows up.