I haven't had time to *really* get into my Gemini until this week because I was under heavy deadline pressure, but over the next month I intend to see what I can do with it, writing-wise.
Interestingly, Termux provides a pretty comprehensive Linux CLI environment under Android on the Gemini. If you're used to the classic UNIX command line, being able to load up NeoVim with a bunch of plugins, git, Python, ssh, clang, and all the usual tools makes it feel rather familiar (while keeping Android around for the driver support that isn't completely there yet under Debian).
termux-setup-storage lets you access files off your SD card or other configured storage under Android. I'm using DropSync to synch a bunch of work projects (mostly big documents written in markdown) with my main macOS and Linux systems; with a 400Gb Sandisk micro-SDHC card installed I've got plenty of elbow room (for music and films and general entertainment when I'm not working). If you want a modern productive IDE you could dip a toe in the water with SpaceVim (although personally I took one look at it and fled screaming back to my old school setup).
Word processing ... forget Microsoft Word. It works, but it's a bit pants at keyboard navigation: instead, TextMaker HD has reasonable keyboard support and most of the features of an older desktop Word, including editing multiple files and change tracking. (But? It's still Word-document-centric; for most work, I'm sticking to NeoVim.)
Anyway: using an Android system as a basis for a Linux CLI text or coding experience may seem a little perverse, but it's possible and even fun. And this is the best kind of pocket linux fun you can shove in a jacket pocket.