* GitHub does render .org files just like Markdown!
* I've heard people of people being really happy with Orgzly on Android.
I personally run Emacs on my Android phone through Termux. It works really well for me.
Other solutions include using a SSH client to connect to a server running Emacs, or simply using GitHub directly on mobile web or their app if your notes are on GitHub.
* I've made the switch from Vim to Emacs (+ evil-mode) because of org-mode and have been extremely happy with it. It truly changed my life.