I'll preface this by saying that I am responding to this five years later, and I'm not 100% sure if this would have been desired (or possible, for that matter) back then. I'm just sharing how I got around this problem in 2022. :-)

What I do for my mobile org-mode needs is a Pinephone with a keyboard case running PostmarketOS with the SXMO environment and Emacs installed on it. It's a full, no-compromises X11-based Emacs setup. 

It's actually quite comparable to an Atari Portfolio in form factor, as opposed to a more typical smartphone. Because my cell phone provider doesn't support the Pinephone, I don't use it as an actual phone, however.