I was tired of pressing the power button whenever I need my phone for a second. Thus I created the Gravity Screen Off app which can turn automatically the screen ON when I grab my phone and turn it OFF when I put it into my pocket or onto a table. Basically, no need to touch any button and you are ready to go.
HOW IT WORKS:
The app turns the screen off by monitoring the orientation of the device through the gravity sensor. When your phone is pointing downward by its top, below a certain angle, it's likely to be out of use. In this situation the proximity sensor is activated to determine if it is covered. If yes, the screen turns off because probably you placed the phone into your pocket or onto a table.
The screen turns on when you lift up your phone. The phone wakes up if the proximity sensor is uncovered or if it was not covered the app is looking for movements to detect the action.
The Keep Screen On feature based on screen orientation and motion detection as well. If the device is pointing upward and small movements are detected it's probably held in hand and the screen timeout is extended.
- Pocket Sensor: Recognizes if your phone is in your pocket. By turning your phone below the angle you set, it'll prepare to turn the screen off.
- Table Sensor: Detects your phone is lying on a table and turns the screen off.
- Turn Screen On by Motion: If the screen is off and it's facing up the device can be woken up by any movements (ex. lift up by hand) according to the sensitivity set.
- Keep Screen On by Motion: It's a Screebl like feature but it's relying on the small movements you are doing by your hand while holding the phone. If small motions are detected while the screen is facing up the feature keeps the screen on because it can be suspected that the phone is held and probably you are reading something. If the phone is steady the timeout will work as normal in any position you leave your device unlike in another apps.
- Turn Screen On by Proximity: Turns the screen On when you take your phone out from your pocket and Off when you put it back. By swiping your finger over the proximity sensor the phone can be woken up as well.
- Turn Screen Off by Proximity: If the device is pointing downward it takes the proximity sensor into account. By turning this off the program will rely only on the gravity sensor.
- Tasker, Llama, Locale supported by plug-in.
- 3 widgets/shortcuts: (available in Unlocked version)
(ii) turn screen off: It's like pressing the power button
(iii) turn screen off persistently: turn screen off and keep it off until power button is pressed. It's good when you have to keep the phone in your hand or while driving and do not want the screen turned on by the app. After pressing the power button it will work as before.
- Power Toggles plug-ins
You can set the app to minimize the energy consumed by the screen and by this you can extend your battery life. Or you can extend your own life by using another features of the app In the first case the battery usage should be not significant. I experienced about 7 per cent extra consumption on the test device. However it can be higher if you are activating often the Turn Screen On by Motion feature by leaving your device face up on table and you set a relatively long timeout for the feature. Read FAQ  for more details.
On some devices if it's lying face down the alarm clock is switched off by the app after it had gone off! Please check if it's the case for you. If, yes, use a third party app, for example: https://play.google.com/store/apps/details?id=com.vp.alarmClockPlusDock
Probably not all feature will work for everyone. It was tested so far mainly on Samsung devices with stock rom. If you think it does not work for you, please read the FAQs below or report your issue in this thread.
REPORT YOUR ISSUE
If you have an issue, do NOT post it until you read the FAQ below and try to solve it alone by trying different settings for some hours. If still no solution, please write all your settings in your question otherwise your question will be ignored. If you feel you have a battery drain, do not post it in this thread. We are not speaking about it anymore
VERSIONS: FREE vs. UNLOCKED by IN-APP PURCHASE
In the Unlocked version, there is no 15 minutes limit for turning the screen on by motion and the Table sensor can be set more precisely, plus it has an Exclude App list, a more advanced Delayed lock option and Widgets.
Thanks to @remidesroques and everyone who helped and keep helping the development by testing the beta versions, sending feed backs or any another way supporting this app.
Spanish: Johandri Silva and Eduardo Iñiguez
Russian: Gljadkov Oleg
Czech: Jaroslav Vrána
Portuguese (Brazilian): Irwing Junqueira Braga