I also use MiXplorer, and wouldn't be able to read my camera's SD cards on my phone without it because Android doesn't support exfat for some reason. Root is required for it to use its own filesystem drivers of course.

I don't think I knew it was on the Play store. It's a free download from the website, but paid on the Play store. I'd like to make a donation without giving Google a cut - the author deserves to get paid.