For us Emacers, one of the longstanding shortcomings of iOS and, to a lesser extent, the Android ecosystem is the lack of an Emacs app. There are several Org-mode centered apps that allow you to perform various Org functions on your phone and sync the results with your computer through the cloud.
Álvaro Ramírez has another offering in this space. His Plain Org app provides a nice interface to Org’s task lists on your iPhone. Take a look at his post to see some animated Gifs of the app in action.
Until we finally get a native Emacs on iOS, apps like Plain Org will get us by. In the mean time, having a decent Org app is a boon. Most of what I want to do on my phone that involves Emacs involves some sort of Org file so having a good Org implementation that syncs back to my computer’s Org file is great.