I’ve just released a new course on Ohmify.
It’s a super practical course where you’ll learn to build a portable USB charger. It lets you charge your phone from standard batteries you can find in any super market.
To build it, you must know how to solder (which you can of course learn on Ohmify).
Check out the new course here: https://ohmify.com/courses/build-your-own-portable-usb-charger/
Keep On Soldering!