If you are using flip cover or flip case with your phone, Cover Lock is just the thing you need.
Simple Cover Lock give you the easiest and simplest way to configure and use.
1 Lock and turn the screen off when your screen is covered. (Covered by flip cover, flip case. Or if you don't have a flip cover, just put the phone in your pocket. )
2 Turn on the screen when you open the cover. (Configurable)
Device administration is needed to lock your screen.
To uninstall Simple Cover Lock, you have to disable it as a device administrator first.
If you're using Samsung devices, you can do that in Settings-Security-Device administrators. Uncheck "Simple Cover Lock" and deactivate.
After that, you can uninstall it like normal applications.
Tested on Galaxy Note 2.
1. Added an option to disable auto screen off when in landscape