"Safe Mode" on Android smartphones is a special operating mode that boots the system with the software configuration at the time the terminal was shipped. Since it is possible to start a terminal with a minimum configuration, it is used for the purpose of investigating system instability factors.
System instability factors include phenomena such as sudden system inoperability (freeze) and repeated app crashes for unknown reasons. If you can't solve the problem by reviewing the system settings or deleting the app you can think of, safe mode is used as a solution.
While starting the device in safe mode, basic functions such as Wi-Fi/Bluetooth communication and calling remain the same, but only the (pre-installed) apps prepared at the time of device shipment can be used. The widget will also disappear. If the problem does not occur when booting in safe mode, it can be determined that the application installed later is the cause, which is useful for isolating the problem. Additional apps cannot be installed in safe mode, but they can be removed, so it can be used as a means to remove apps that cannot be removed in normal mode.
To boot into safe mode, press and hold the "Power off" icon that appears when you press and hold the power button for a few seconds, then tap the "OK" button in the "Reboot to safe mode" dialog that appears. (This may vary depending on the manufacturer and model). If your device is powered off, press and hold the volume down button until the animation ends. After a while, if the home screen with "Safe mode" displayed at the bottom appears, booting in safe mode is complete. You can exit safe mode and return to normal mode by powering off or restarting your device.