Turn your old Android phone into a free car theft alarm and use this application, Car Theft Alarm Control, for controlling the alarm device. In addition to this, you need a free alarm application, Car Theft Alarm. You can find it here: https://play.google.com/store/apps/details?id=akira4apps.carthieftrackerInstructions:1. Install Car Theft Alarm to your old phone which you can leave into your car to detect movements. Start the application.2. Install the control application, Car Theft Alarm Control, to your current phone. Set the phone number of your old phone to the settings and click REGISTER.That's it! Now you can activate alarm using Car Theft Alarm Control and/or check the location of your car when ever you want to.NOTE!Car Theft Alarm and Car Theft Alarm Control communicate with each other using SMS messages when Bluetooth connection cannot be used. There will be no unneeded messages, but SMS messages will be sent only when you give new command for the alarm device or when alarm goes off. Feel free to send an email to me if you are having problems using the application or you suspect you are seeing some error in the app!