Developer's description of the app:
Cerberus helps you get back your lost or stolen Android device.Cerberus is a complete anti-theft application, the best protection you can get to recover your misplaced, lost or stolen Android device. This is a free trial for one week, then you can buy a lifetime license for a small price (2.99€) from within the application: no monthly or yearly fees, just a one-time payment. License is associated to your Cerberus account, if you have multiple devices you can use all of them (up to 5) with the same account.
To get the license, just download the app and register for a free account and fill up the form at the Google Docs page.

App page:

Promo page:

Enter your Cerberus username and email address to get a free license. Promotion ends at 23:59:59 GMT, February 29 2012. Email address is required, so we can contact you if there are any problems activating your license. All licenses will be activated on March 1.

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