Samsung Galaxy S3 will not reboot I have a Samsung Galaxy S3. 

For the last couple of days, it has been freezing quite regularly. I had to hold the power button and reboot, sometimes more than once. The last time I tried this, the device would not reboot. It turns on, shows the S3 logo, vibrates, and keeps the LED constantly blue. However, it does not get any further than the Samsung logo. It just keeps the blue notification light on and the Samsung logo slowly flashes blue. 

Can someone help with this?
I cannot tell for sure what is causing this, but there are two things I can think of as a remedy:


Try booting into Safe Mode (see Android Safe Mode in Galaxy S3 for details if you're unsure). If that is still possible, think whether you've installed any app just before your problem started -- and delete that app from within Safe Mode. Reboot to leave Safe Mode and see whether your problem has been solved this way (hopefully it has!)
Last resort: Factory reset. This will delete all data and all the apps you've installed, and make your device "virgin" (see Hard-Rest.Com for details on how to do this).


I suggest trying the Safe Mode part right away as it does no harm. If it solves your issue, you're done; otherwise you might to wait a little more for alternative answers here before going for the Factory Reset -- maybe someone else has an additional remedy to offer.