It's called OSP. Short for On Screen Phone.
Your phone will have to be on the same network as you computer.
A simple Google search of "OSP LG G2" should give you a nice step by step guide.
I use it daily and it's quite responsive and snappy.
Also, if you are able to set it up you could also try the "wireless storage" utility. Enable it, type \\g2 in explorer and it opens the internal storage folder.
Take a look at the "delightful discoveries" thread in the G2 General section. Prepare to be amazed
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