I find that for a true productivity tool, I'm fine relying on my desktop & laptop. I'm actually dialling back what I use my phone for, simply because I can't trust either of the major mobile OSes to respect me & my privacy. It would be awesome to have all of org available on a phone though; you're not wrong at all there.
I would kill for an emacs which makes sense on mobile, but I've not given enough thought to it to imagine what would make sense. Emacs without the key chords would be still powerful but also odd.