Hello Guys!!
Have anybody missed AUTO BRIGHTNESS feature in L9 because lack of Ambient Light Sensor
If yes, the don't worry. I have an easy solution for Auto Brightness, Yes you can use Auto Brightness on LG Optimus L9:victory:
NO ROOT REQUIRED
Download and install These two app from following links:-
Lux Auto Brightness
Tasker
After Installing these apps follow these steps:-
Lux Auto Brightness:-
* Go to Lux settings
* Tap on Sample Collection
* Tap on Select light reading source
* Select Camera
* Then get back to main settings menu
* Tap on Mopdify linked samples
* Tap on Luma TAB
* Tap on ADD, set brightness (yello bar) to 4% Luma value to 1 and press ADD
* Add 3 more links with these values= 35%-70|100%-80|50%-120|
* Exit Lux
Tasker:
* Open Tasker, tap on Plus Gign(+) on main screen
* Tap on Event
* Select Display in Event Category
* Select Display On in Display Event
* A blank screen will appear, do nothing just press BACK Button
* TAP on New Task +
* Enter Name to task or just tap on tick
* A blank screen will Appear, tap on Plus Sign (+)
* Select Plugin from action category
* Select Lux Plug-in
* Tap on Edit Button
* Scroll Down and Tick in front of Refresh Backlight brightness? Under Force
* Press Done, then press back and back again
* Exit Tasker
Thats all work to do, now your dvice have Auto Brightness feature:silly:
To test, just press power button and lock the screen and then cover front camera with finger and press power button again, screen will Light up wait 1-2 seconds, Screen brightness will reduce, remove finger, lock unlock screen and brightness will resume to normal.
I have tested this for full day on my L9 and got no any battery drainage.
You can modify Linked Samples Values to your comfort zone for batter sample values you can also search other XDA forums.
Guys try it and let me know how you feel 
if you got any issue please post, I'll try to solve it (Coz m also new to TASKER & LUX so may be it will take little bit time to Solve:fingers-crossed
EDIT: You can uncheck "Presistent notification" in general settings of Lux Auto Brightness, If you think it is draining your phone's battery. This will also disable the annoying Lux icon from notification.
All thanks to gdjindal at xda forums
