Hi,
I have an iphone 7 to use with the mavic, that is on order. I was going to order a Ghostek Atomic 3 series case to protect the phone from scratches while at places like the beach. I have noticed that the lightening connector plug on the atomic case will need to be open so it may not fit the Mavic controller cradle arms.

Are you using this case or can you recommend a different case?

I use the UAG case with no problems and its the iphone 7 plus. You might have some difficulties with the case you plan to order since that lightening access port is so small and has that rubber piece to work around.

Thanks for the info - I'll be getting a bumper style cover.

This is the best case for an iPhone 7plus. And the best part is it's only $7.00 on eBay. I'll provide you with the link and some photos. I personally love it.
http://m.ebay.com/itm/HYBRID-360-HARD-ULTRA-THIN-CASE-TEMPERED-GLASS-COVER-F-IPHONE-7-6-6S-PLUS-5SE-/262428359314?var=&hash=item3d19f2fa92%3Am%3AmIo9DZRdgFOZ6WaWxIyVrbw&_trkparms=pageci%253A9799bbcb-bb6e-11e6-b141-74dbd18032fc%257Cparentrq%253Ad271f9291580a62293a2c613ffe30554%257Ciid%253A1

The link did not work. Here's the eBay item # 262428359314
It comes in a few colors as well.