Just unpacked my Phantom 3 4K : )
I notice the app appears to be working without being connected via USB between the tablet and controller.

Is the USB link only required for software updates or is there USB data flow during operation?  It would make sense that all three devices communicate over wifi, but I'm seeing Youtubers with the USB connected and the manual is't clear on this - only for updates.

Thanks

Mick

Only one way to find out... Did a test flight and fired off some stills and video - adjusted a few settings.  Result: No need to have a USB cable connected between your mobile device and the controller during operation.

Hi . Mick
The Phantom 3 4k uses WIFI transmission , you'll not need to connect your device to RC in your flight .