I don't think this has been mentioned but I like it a lot even though it does just one quick task: Screen Off
Usually when you are done with the phone the screen stays lit for 30 seconds or more (depending on what you've made your setting) while you are not using the phone or have put it in a pocket.
With this app you just tap the icon and the screen immediately turns off.
I like it a lot.
BTW, great forum. Newbies like me can really learn a good deal about these amazing devices.