DIY, assemble a bag or box of goodies to keep with you for data and power transmission at any time, with any device.

Electronics Kit – Build your own box of goodies:

 

Electronics Kit - PDF

I carry a minimum of:

Power cable USB-A to USB-C w/adapters for USB-Micro and Mini as well as Thunderbolt Cable

20,000mAh Battery Pack

USB and microSD cards with critical information, as well as an adapter to plug these into a phone

110V and 12V USB Charging Adapters

Yubikey hardware token

 

I also frequently carry a slightly larger kit in a small plastic box with extra adapters and cables, USB sticks, ethernet cable, wifi adapters, travel router, and a lot of other random electronics gadgets. This allows me to stay powered up, and transmit and store data on the go

Also carried with me frequently is small amount of cash for emergency, as well as prepaid VISA gift card