Yes. I have a Boox, and I’m quite happy with it. I don’t use many android apps, but the killer app for me (why I got it over a Remarkable or Kindle Scribe) is being able to run a Zotero-compatible app (Zoo for Zotero) with bidirectional sync for reading and marking up PDFs.

There are but OP doesn't appear to be using e-ink, it's much too fast to be that. I would guess it's an unorthodox form of LCD display.

It’s reflective LCD (RLCD).

But with a backlight, which is novel I think?

Reflective LCD with backlight is called "transflective LCD" and they have been in use for years: https://newhavendisplay.com/blog/transmissive-vs-reflective-...

Ohh neat. Like the Playdate

Yeah the Playdate screen is lovely, but pretty rough without a backlight.