Safe Mode is a feature on the Android Operating System used to solve problems with configuration or app incompatibilities
Android phones have a Safe Mode that can be activated by turning it off and then turning it back on while holding a specific set of buttons, typically Volume Down + Power. Once you enter this mode, other programs are not running and cannot cause problems with either software or hardware. Safe Mode also allows you to work in an environment with no applications installed until the original problem has been diagnosed and fixed. The other advantage of safe mode is that many apps for Android including Facebook, Twitter, WhatsApp etc which usually run all the time in the 'background' will stop working totally while in this mode so you can easily consult friends or colleagues.