Power Button

Power Button (Package Name: org.torcellite.powerbutton) is developed by Torcellite and the latest version of Power Button 0.5.1 was updated on December 18, 2014. Power Button is in the category of Tools. You can check all apps from the developer of Power Button and find 64 alternative apps to Power Button on Android. Currently this app is for free. This app can be downloaded on Android 2.2+ on APKFab or Google Play. All APK/XAPK files on APKFab.com are original and 100% safe with fast download.

This application requires root access. Your Android device has to be rooted for this application to work.
Please add Power Button to the ignore list of the task killer if you have one installed.
If the HUD doesn't appear or screen on feature doesn't work, open the app again to bring them back.
The application maps your Power Button for easy access on screen. You can set a widget or notification (HoneyComb and above only) for turning the screen off and opening the power menu. You can also access these functions from within the application.
The application has a quick setup to help you with how the application works.
It will try to automatically map your power button, failing which it'll show you the output of the devices present on your phone. Please choose the one which you think is by best the power button. This happens because not all devices have their power button mapped under the name "pwr_key", some of them like the HTC Wildfire use "keypad" and so on and so forth. So it is hard to manually map all possibilities. Do try out every one of the devices listed if you're not sure and test them all out, one of them will DEFINITELY work.
This application has been personally tested by the developer on the Nexus 4 running 4.4 and HTC Wildfire running 2.3.7
This application was also tested by Jasper Guerrero on the following devices :
Nexus 4 (4.4.1), Galaxy Y(2.3.6), Galaxy Ace I(2.3.6), CM Titan(4.1), Sky Vega(4.0.4), CM Burst(4.1.2), Galaxy Y 2(4.1.2), Galaxy S2(4.2.2), Galaxy Ace(2.3.7).
Thank you, Jasper.
Jasper had the following to say about the application's new version:
Cons first:
-Response in screen off is kind of delayed compared to v0.2. Both in status bar and in widget.
Pros:
-Easier set-up
-More friendly
-Faster access having widget and notifications
-Mapping is faster since SU is granted in the first place.
The slow response time is because there is no service running in the background that consumes battery. When you access the widget or notification, the app is called - it turns the screen off or opens the power menu - and then immediately terminates. Thus, there is almost 0 battery consumption.

Power Button 0.5.1 Update

v0.5.1
*Added in-app purchase to remove ads
v0.5
*Added shortcuts
*Added translations for multiple languages, if you find many mistakes in the translations and would like to correct them, do contact me.
v0.4.7
*Fixed crash on Android L
v0.4.6
*Minor bug fixes