How to Restore a Stuck Samsung Galaxy S, S II or S III
Samsung's Galaxy S, S II and S III smartphones have a few tricks to get a locked-up or stuck device back in working order. When the GS device is stuck, it usually means that the operating system or an app has encountered an error from which the device can't recover.
1 Perform a Soft Reset
A soft reset may restore a stuck GS. If the phone is frozen, you can force it to shut down by holding the power key until the device cuts power; otherwise, press and hold the power key, tap "Power off" and select "OK" to shut down the device. Next, remove the back panel, take out the optional MicroSD card and remove the battery for 30 seconds. Reconnect the battery, return the back panel and turn the device back on.
2 Enter Safe Mode if Stuck on Boot
If the GS is getting stuck shortly after turning it on, the device may be locking up because of a problematic app. You can stop problematic apps by booting into "Safe Mode" and uninstalling apps you suspect are freezing the device. To enter Safe Mode on the GS model, hold the "Menu" key while turning on the device. You can enter Safe Mode on the GSII and GSIII by holding the "Power/Lock" button for two seconds to power on the device and holding the "Volume down" key when the Samsung logo appears until the lock screen displays.