Hey i just go the phantom 3 advanced and i cant get it to connect to the mobil app on my iphone 6 and i tryed changing USB chords someone please help.

I had this problem on my android, Xperia Z2. But the minute i turned on USB Debugging and it worked instantly. Hope this helps.

Plug in the cable.

1) After you have your advanced and your RC on, is the light on the RC green or red?  You might need to re-link the aircraft to the RC.

2) You have to register your aircraft with DJI first.  If the Camera View is grayed out and you cannot enter you probably have to register.  But if you can click and enter the GO app and it displays disconnected at the top then you probably need to re-link like I mentioned in #1.

Ensure that the App is installed. Connect the iPhone via Thunderbolt Cable. Ensure that you have an Internet connection to the iPhone. Power up the Controller and iPhone. Remove the Props if they are on. Power up the Phantom. You should receive an activation window. Complete that process. It may take a minute or two to link everything.

If the above fails, call Apple Care. There may be something in the Phone that is on or off.
Let us know how you make out.
Good luck