Wouldn't it be good for Mavic to have the portable charging station like the one just came out for the Spark ?
Staying out of home with 3 batteries means we only have 1.5 hours of flying time, and it is great if we can fly another 1.5 hours after 2 hours of charging time even without an external socket.

DJI please really consider that.

I use one of these. They have intelligent USB charging etc. Might be worth a look.
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Hi, sounds like a good idea, but I think it may hard to be realized. Anyway, will forward it to the engineers.

i will be interested by a device like this proposal

I don't really like the idea, don't you feel it's stupid to buy a Spark charging station, with 2.8 times price and 7 times weight of an extra battery?
You just need to buy more batteries.