MiX file explorer for android does this. It's free. Not sure if it's open source though, does anyone know?
It does use open source libraries.
Latest version is 6.64.3 beta.
https://forum.xda-developers.com/t/mixplorer-q-a-and-faq-user-manual.3308582/
"MiXplorer (Mix of Explorers) is a fast, smooth, beautiful, reliable and fully-featured file manager with a simple and intuitive user interface." created by XDA member and Recognized Developer @HootanParsa
I second Octavia Butler.
On my list to read, but haven't yet, is N.K. Jemisin.
A fairly new author is Malcom Turnbull. He was on a radio interview a while back and the book (The Lesson) sounded interesting so I gor it and read it.
A lot of the sci-fi books I've been reading lately have black [main] characters. I don't know if those authors are black though. I have to look into it.