The old traditional way of monitoring a security system was based upon a phone line. With increasing technological advances, cellular back-up devices have been created to eliminate the use of phone lines. Commonly today, many individuals commercial and residential no longer utilize phone lines, however cellular back-up devices have made it possible to have no interruption in service regardless of phone lines dropping or being cut. A large majority of these cellular back-ups provide remote access to your security system via an app compatible with both Apple and Android. In addition, the cellular back-up device can allow certain issues to be troubleshooted via phone call with a technician versus a service call.