In general, I like to use the power card that comes with the device. In some cases, it is mandatory because the cord has a power brick on it that is specific for that device. Apple makes it relatively easy with the lightning port. I can charge my iPhone, iPad, AirPods, Apple TV remote, and Apple Mouse all with the same cord. The MacBook is the exception with the bigger USB-C port. 

I don’t mess around with cheap knock-off power cords sold on Amazon. I have read horror stories of someone trying to cheap out only to fry an expensive device. I use genuine Apple cords with Apple devices and that’s that.

When it comes to non-Apple devices there is more variety. The Kindle charges with a different cord than the Sony earbuds. I don’t know how many different ports there are, but there are enough that my travel bag can get out of control with cords everywhere. If one cord can charge multiple devices, then I will just take the one cord. After all, these cords all have USB ends on them, so it’s not like there is a special power brick that is designed only for that device. 

Also, I don’t know if it matters what that USB end is plugged into. I usually just use the Apple plug connector because I have more of those than any others. When traveling, I avoid plugging directly into a USB port at an airport or in a hotel. Again, horror stories of people somehow modifying these ports to spread malware and viruses.