Dear Dji,

I noted the following bug with latest firmware:

When trying to fly the Mavic using the DJI Go4 App and an iPhone 6 connected to the RC, I lose video transmisstion and all other information on the phone (same effect like if you would plug the cable out) IF I fly and my cell phone has an EDGE connection to the cell phone network. This does never happen when I have a 3G or 4G connection.

If you need further information let me know,
Best regards,
Steve

Weird. Maybe the EDGE spectrum interferes with the Mavic's radio? Lots of folks apparently switch their phones to Airport mode before flying, sounds like this might be a good workaround when you are in an area where you fear it may switch to EDGE.

I always switch to flight mode now after my wife called me during a windy flight down the beach and I nearly ditched it in the sea

Great tip.
That's excactly what I do now, switch to flight mode. I don't know if it's a bug or real interference. But I'm happy to know at least why this happened a few times to me.

It is so weired