Just read the threads in the android development section?
Those will answer all of your questions?
Or just google it?

Is this so hard that you have to open up a new thread for this?
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|| LG Optimus 4X HD (P880)
|| Android Version 4.4.2 Kitkat
|| Recovery TeamWin Recovery Project 2.7.0.0
|| Kernel Iodak 9.95 (patiently waiting for v10 )
|| Rom Version Beanstalk 4.4.275 ported by Ecto

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