Step into Safe Mode: (here Samsung Galaxy On 5 do Found)
1. Turn off your cell phone, make sure your phone able to boot and has enough power.
2. Press the power button, open the phone, wait ... .
3. When the first boot animation disappears, immediately press and hold the phone's menu button and hold until the phone into the system .
4. After entering the system, which is the Samsung i9300 safe mode, lower left corner of the phone screen will display "safe mode."
(Close Samsung i9300 safe mode is also very simple, and then shut down the normal boot can be.)