Just take more SD cards and throw the little lock once filled and store them away. Get a nice, small weatherproof case like a Pelican #0915 for storage (I can stack two SD cards in mine where one should go.).
I went the phone route but it was slow and really eats into my data cost (Overages=$$ or throttle-downs that take hours!) with large RAW transfers. JPEG wasn't bad, when I had a signal.
The S6 Edge I have doesn't have a removable card and only has about 30GB available out of its 64GB with the apps. Kingston Memory makes something called a MobileLite which is a wireless drive from the phone to a SD card for storage (Phone needs their MobileLite app too). Still, even with the small (pocket size) MobileLite, a case full of SD cards can't be beat for speed, less wear and charging of the transmit device (camera phone and MobileLite both), and the down-time needed to do a transfer, and then charging everything up again which takes hours. Just pop in another card and keep shooting.
More cards!
SG