As in title, preferably open-source, but doesn’t have to, I will start:

KOReader - Amazing reader app, and being able to use the same app across various devices, even non-android ones, is pure bliss. Japanese support is pretty good too, which makes me happy. Though… Sadly no vertical text support :c

Syncthing-fork - Being able to keep a library of books, and some files, and easily keep the shared folder across various devices, is mega comfy. Tachiyomi - Cute manga reader.

NewPipe - Really pleasant youtube client, that i sometimes use to listen to things in the background.

Kaku - An useful Japanese OCR app, that works… quite decently for when I encounter kanji that I do not recognize, and is not text.

EinkBro - A web browser, that on e-ink devices, is quite comfy. Has few… quirks, but works well on e-ink

  • I would say… Termux/SSH clients, as they are text based… Tachiyomi, with disabled animations… But beside that, not much. I just abuse the fact that e-ink devices that I do have, do refresh the screen at decent speed (e.g Hisense A9, Onyx boox Tab Ultra), so… most apps are actually useable, even if… the experience on other devices would be pure misery.

    Sorry for not being able to be much of help #_#