I have no idea that manufacturers are so freaking stupid!!!!
I got an LG Optimus X4 from USA (that was imported from some place else, unknown to me)
The phone never found any 5Ghz N networks so I assumes it wasn't supported
it worked fine with WiFi N at 2.4Ghz, then yesterday it stopped! For no reason, nothing changed same SIM card.
But it connected to WiFi B/G without any problems.
I assumed something happened on hardware level, because people with similar issues couldn't connect to no networks at all
I wasted whole day installing crap wifi fixers and updating/ROMS and nothing.
Until I found this app, now it find both 5/2.4 N networks and connects to both
So thank you!