I don't think all USB-A chargers are created equal. I know that if I plug my iPhone in with the official charging brick, it'll charge maybe in an hour or so.

I don't think all USB-A chargers are created equal. I know that if I plug my iPhone in with the official charging brick, it'll charge maybe in an hour or so. If I plug it into the USB outlet in my car ... I'm looking at much longer. Some background on how Apple "detects" their own charging bricks: https://learn.adafruit.com/minty-boost/icharging https://learn.adafruit.com/minty-boost/icharging However, for USB-C, I'm sure any charging brick will do.