Vim is available on android through termux. I've used it to write a few things. I actually used it to wrote an app to access my city's transit api because I wasn't a fan of the available ones.
With the right keyboard installed it's actually not too bad. Best programming editor i've actually found available on android.
My main reasoning was, I use the bus when i'm out and about, I don't carry a laptop with me most of the time, I was unhappy with the way the bus times were displayed in the available apps, so I wrote it on my phone at work when I had a bit of time.
Most of the other things were just playing around with the limited access to the android api termux gives you. I actually prefer SL4A for android scripting, but it's been dead for years. It granted access to more of androids api than termux does though.
They're designed for use independent of a keyboard. So yes, when you just want to stab at the screen and smudge it with skin oil, you can.
My preferred keyboard is a folio case with an integrated keyboard. I can pop this into a tent-form laptop, or, in a fraction of a second, flip the keyboard out of the way and use just the tablet. No hinges to break.
Major con: There is absolutely no standardisation of tablet form factors and corresponding case and keyboard designs. I've found this maddening to no end. Existing keyboards without exception suck, and Logitech sucks even harder. That said, this doesn't have to be the case.
Either portrait or landscape orientation, without preference on the device, oriented by accellerometer. Inverse portrait/landscape as well.
Incredible battery life. Generally, all day, with heavy use.
Tablets are virtually ideal as communications devices, so long as you're not actually in motion. I might carry a small dedicated phone in addition just for voice comms (restricted to a close whitelist), though in practice I prefer batching my comms and not being interrupted 24/7/365 without relief.