When comparing OmniFocus 2 vs Emacs Org-mode, the Slant community recommends Emacs Org-mode for most people. In the question“What are the best cross-platform task apps?” Emacs Org-mode is ranked 3rd while OmniFocus 2 is ranked 36th. The most important reason people chose Emacs Org-mode is:
This app's flexibility is based on its minimalist approach, giving the user near-infinite freedom.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Organize tasks into projects
OmniFocus 2 allows you to organize tasks into Projects, allowing you to keep your tasks organized in the best way to stay efficient for that project. Each task also features summary dots. For example, red means the task is overdue and orange means its due soon. There is also a range of other dots that can be specific to projects.
Pro Forecast summary
The Forecast Summary shows a quick glance of the tasks you have that day. You can tap on any day to quickly see what tasks you have planned that day. For extra functionality you can connect the iPhones Calender app, which allows you to also see any other events you have planned that day.
Pro Excellent full stack support from phone, to tablet, to Mac
With very good synchronisation.
Pro See an overall view of tasks via "Perspective"
The Perspective section allows you to see an overall view of the tasks you have set. It also allows you to set contexts or see things you have flagged.
Pro Superbly customisable via Perspectives
Pro Picks up reminders added via Siri
Pro Best support for GTD in the marketplace
This really supports the implementation of David Allen's Getting Things Done
Pro Nearby and context-sensitive tasks
OmniFocus 2 allows you to set up contexts for tasks in certain areas. This makes sure you never miss a task when you're out running errands or happen to be near something you need to do. Just set contexts around places you frequent or set as a specific task.
Pro Client side encryption
Pro Apple Watch integration
You can send lists from your iPhone, and get notifications on your watch each morning with any tasks you have set for that day.

Pro Ultimate flexibility
This app's flexibility is based on its minimalist approach, giving the user near-infinite freedom.
Pro Absolutely free
Emacs with Org-mode is free as in beer and free as in speech – that is, it costs nothing and it’s totally open source.

Pro Files are usable anywhere at anytime
Users are not tied to one service provider, program, platform, or database engine.

Pro Incredibly extensible
There are many plug-ins for Org-mode, including Org-habits and Org-notify. If Org-mode lacks some piece of functionality, it is very easy to add it.
Pro Agenda views
Pro Excellent unofficial Android app (orgzly)

Pro Offline support
Pro Efficient features for deadline organization
Pro Supports plaintext spreadsheets
Pro There are a lot of extensions, for exporting to html, bootstrap, js-reveal and much more
Pro Quickly add rich text
Cons
Con Very expensive
$40 for a to-do-list app is a bit much, even with all the other features it offers.
Con Limited to Apple devices
Must be used as a native Mac, iPhone, iPad, or Apple Watch app. There's no cross-compatibility with Windows, Android, or web.
Con Only one context (tag or label)
This won't stay a con for long. With the pending version (Omnifocus 3) to be launched in 2018, Contexts are being replaced by Tags. Yes, finally...you can have as many contexts as you like for a particular action.
Con Slow sync in Europe
Con Unintuitive user interface
The key combinations are unintuitive and difficult to remember. This is probably because there are a lot of hidden "modes" depending on where the cursor is. Actions aren't paired with reversing actions like in other todo apps. For example, hitting shift-tab does NOT reverse the effect of hitting tab.


Con Android app isn't very good
There are several user-created apps for Android, but none seem to offer the same level of functionality as other to-do apps.
Con Not really cross platform
Although it is possible to get a lot of it working, no all in one, sync included, out of the box solution is available for mobile devices.
Con By default, a hard-to-read display
The default way of writing an outline or checklist creates a very messy wall of text that's difficult to read with no vertical spacing. You can manually add vertical spacing, but the Org operations don't preserve it. There are pretty-display modes, but you need to remember how to enable them, etc. etc.
