If you're having issues with your Android device and trying to work out which app might be contributing to the problem, use this trick to boot into safe mode. Doing so will load the Android OS without any third-party apps.
The How-To Geek shares two methods to boot your Android device into safe mode: If you have Jellybean (4.1 or later) long-press the power button until the power options menu appears and then long-press the power off button. You should be asked if you want to reboot your phone into safe mode.
On older phones (or Jellybean phones that don't work with the previous technique, like my Samsung Galaxy Note II) simply reboot your phone and hold down both the volume up and volume down buttons while the phone is booting. The words safe mode should appear on the bottom of your screen.
If your phone doesn't have the same issue (crashing, freezing, battery life problems), then you can be reasonably sure it was caused by a third-party app. Try uninstalling your most recently added apps first, and you should eventually find the culprit. If you're still having the same issue in safe mode, you may want to restore your phone to factory settings. For more details, visit the source link below.
How to Boot Your Android Phone or Tablet Into Safe Mode [The How-To Geek]