It does only work for a subset of org-mode functionality, but for TODOs and similar I find Orgzly on Android works great. I sync between my laptop and phone via Syncthing.
I use emacs from termux frequently, even better if I use my bluetooth keyboard and hdmi out to a tv, but even though the text is small in normal mode I still prefer it to any of the fdroid emacs or org mode packages.
For those who worry about runaway configs, I highly suggest starting with sanemacs for a good minimal configuration you can start with and build from a good foundation on.
I find the iOS app BeOrg great for mobile access to my org mode inbox. It works well as not only a place to write quick notes but also to, say, "share to" links from Safari and other apps to create inbox entries as well to quickly capture URLs to view later.
The stumbling block I usually come to is wondering how to utilize these data sets on my smartphone in an efficient and effective manner.