SOS can save your life. It is an application that notifies the number that you specify by sending an SMS with your exact position via GPS (it includes triangulation by the telephony antennas). In addition, if after the established time you have not stopped the warning alarm, the application will automatically call the emergency phone you have set up and, once the service responds to your call, the hands-free (Speaker) will be activated so you can communicate without have the phone in your hands