Mobile theft is a common problem which leads to the loss of money and violates personal data. One product that addresses this problem is known as the Anti-Theft System (ATS) developed to work on Android devices. Once installed, ATS automatically establishes a connection with the device and nudges users into inputting another contact number when configuring the application. This system makes use of a database which validates the owner’s name and details of the SIM card. ATS is designed to come on in stealth mode each time the device is booted up in order to validate the SIM card that has been inserted. ATS remains dormant if it establishes that the SIM card is owned by the legal owner as registered with the authorities. On the other hand, ATS silently sends an SMS to another prespecified contact upon the identification of a fresh, unmatched SIM card even though it does not alert the illegitimate user. Also, ATS has a responsive feature that works when certain texting instructions from the owner are searched for. When a command is given it is capable of utilizing the integrated GPS to transmit the exact position information consisting of the postal address of the device in real-time. This feature proves most useful during the post-theft recovery operations. ATS increases device security as it relies on the forceful and widely applied Android operating system to provide its clients with an effective way and confidence in addressing the issue of mobile insecurity.