Emacs vs Ulysses III
When comparing Emacs vs Ulysses III, the Slant community recommends Ulysses III for most people. In the question“What are the best Markdown editors for OS X?” Ulysses III is ranked 4th while Emacs is ranked 14th. The most important reason people chose Ulysses III is:
A few themes are baked in and a big selection of [user-contributed styles](http://styles.ulyssesapp.com/) to choose from are available on the Ulysses Style Exchange.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Keyboard-focused, mouse-free editing
Emacs can be controlled entirely with the keyboard. While true, I often find the mouse and menus handy for those lesser-used commands. An aide-memoir.
Pro Total customizability
Customizations can be made to a wide range of Emacs' functions through a Lisp dialect (Emacs Lisp). A robust list of existing Lisp extensions include the practical (git integration, syntax highlighting, etc) to the utilitarian (calculators, calendars) to the sublime (chess, Eliza).
Pro It's also an IDE
You can debug, compile, manage files, integrate with version control systems, etc. All through the various plugins that can be installed.
Pro Works in terminal or as a GUI application
You can use Emacs' command line interface or graphical user interface.
Pro Self documenting
Emacs has extensive help support built-in as well as a tutorial accessed with C-h t.
Pro Free
Licensed under GNU GPL.
Pro Great documentation
With 30+ years of use the Emacs documentation is very thorough. There are also a lot of tutorials and guides written by third parties.

Pro Vi keybindings through Evil mode
Evil mode emulates vim behaviors within Emacs. It enables Vi users to move inside the Emacs universe.
Pro Provides org-mode
Advanced planning and publication which can start as a simple list.
Pro Enormous range of functionalities (way beyond simple "text editing")
Through its programmability, a very broad range of functionalities can be integrated in emacs, turning it even into a "single point of contact" with the underlying operating system.
Pro Cross-platform
Works on Linux, Windows, Macintosh, BSD, and others.
Pro Integrates planning in your development process
You can jump straight from your org-mode files to programming tasks - and back - and build a seamless workflow.
Pro Versatile
Emacs is great for everything.
Pro Mini buffer
You can pass complicated arguments in the mini buffer.
Pro Ubiquity
Fully compliant GNU-emacs is available on many platforms, and they all understand .emacs configuration files.
Pro Rectangular cut and paste
Emacs can select rectangularly.
Pro Lisp customizations
With lisp customization, any behavior of Emacs can be changed. Update with pre-release patch can be also applied without recompiling the whole Emacs.
Pro Visual selection and text objects with Evil
Evil is an extensible vi layer for Emacs. It provides Vim features like Visual selection and text objects.
Pro dabbrev-expand (Alt-/)
Dynamic word completion.
Pro Support multi-line editing, multiple frame, powerful paren, crazy jumping style
Review the "Emacs Rocks" video.
Pro Has been widely used for a long time
The first verion of Emacs was written in 1974 and GNU Emacs in 1984.
Pro Helm plugin adds even more power to Emacs
Powerful commands, search, and more with the Helm plugin.
Pro GTK+ widgets support
Since version 25 you can run GTK widgets inside Emacs buffers. One of these is the WebKitGTK+, which allows the user to run a full-featured web browser inside Emacs with JavaScript and CSS support among other things.
Pro Excelent tutorial to get you started
The tutorial you are presented with at startup shows you exactly what you need to get started and teaches you how to use the built-in help yourself later.
Pro Interactive Shells
Emacs has a number of shell variants: ansi-term, shell, and eshell.
Pro Emacs provides magit, the best and most complete GIT interface
Complex git history editing become a breeze with very few keystrokes. And simple ones are quickly stashed in muscle memory. Git becomes an direct extension of your brain thanks to Magit. Cherrypicking, blaming, resetting, interactive rebasing, line level commit, spinoff branches... you name it, magit already has it and has typically all those 5 to 10 git CLI commands of higher-level patterns also tide to one simple shortcut (want to amend a commit three commits away ? forgot to branch out and you've got already N commits on master
? ... etc... ).
Pro Gnus
Managing several large mailing lists has never been easier using Gnus. The threading commands and the various ways of scoring articles means that I never miss important messages/authors, etc. A joy to use.
Pro Eshell is cross platform
You can use the underlying operating system shell as a terminal emulation in an Emacs buffer. Don't like the default shell for your configuration? You can change it to your liking.
Pro Excellent Lisp editing support
Built-in packages make editing Lisp source code feel natural.
Pro Use-package and org-mode
Missing some neural package that predicts actions, maybe in the next release ...
Pro Highly customizable
A few themes are baked in and a big selection of user-contributed styles to choose from are available on the Ulysses Style Exchange.
Pro Does not distract the user
Ulysses has a clean, unobtrusive, easy to overview interface that allows focusing on writing. By default it's split up in 3 panes with sidebar, sheet pane and content pane from left to right. Unnecessary panes can be hidden.
Pro No Markdown syntax knowledge required
Markdown formatting can be applied from the right-click menu, with keyboard shortcuts or from an optional markup bar. Necessary elemants to links, images, and footnotes are added by filling in a popover.
Pro Can paste rich text and import from Word
Pasted rich text and imported Word documents keep their formatting when converted to Markdown.
Pro Attachments can be added
Attachments such as images, text notes, keywords and writing goals can be added to content. And to organize them keywords can be added.
Pro Great tools for organizing and finding files
Ulysses saves everything in the app so there's no file management outside of the editor involved. It organizes content in groups (folders) and sheets (files), has a powerful, easy to use search and allows adding keywords to attachments to help them be organized and found quickly.
Groups can have an unlimited amount of subgroups and the title of subgroup shows up in the pane view. Sheets can be split up, merged, glued together and easily moved around in the sheet pane by dragging and dropping. Great for splitting up larger documents into manageable chunks while still keeping an overview of the whole project and having the ability to move sections around quickly.
Contents of a group can be filtered by text, keywords or change date within headings, code blocks, images or any other marked up text. Filters can contain a combination of conditions and be saved to make a new group. Saved filters can be moved around to different groups and will return filtered results for that group. Selecting multiple groups will show the combined sheets of those groups.
Pro Keyboard navigation
You can operate Ulysses via keyboard only. No need for mouse.
Pro Multiple preview and export options
The editor can export to Plain Text, RTF, Word, HTML, ePub and PDF with customizable styles for each option. It can also preview HTML directly in the browser.
Pro Inline formatting
There's no live-preview pane or an external previewer necessary. Ulysses displays styling inline.
Pro Includes features for not losing place
Ulysses has options for highlighting current line, showing line numbers and enabling typewriter mode. Typewriter mode defines a place on the screen where the cursor should be so eyes are kept focusing in one place on the screen.
Pro Syncs via iCloud
Content can be synchronised across devices via Apple's iCloud.
Pro Comprehensive documentation
Ulysses comes with an excellently written documentation that covers everything there is to know about the software, including an extensive list of keyboard shortcuts as well as short and sweet introduction to Markdown and its benefits.
Pro Allows the user to work anywhere and on any Apple device of their choice
Ulysses is available for both macOS and iOS. This, combined with the cloud syncing allows users to work on their projects using any Apple device they have at the time.
Pro Displays statistics including how long it takes to read the document
The editor tracks statistics that shows how many characters, words, sentences, paragraphs, and pages a document contains and estimated reading time for slow, average, and fast readers. The statistics display in a popover that can be torn-off so it's constantly visible.
Pro Helps get stuff done
Goals such as how many characters, words, sentences, paragraphs, lines or pages should be written can be set to help get motivated.
Pro Powerful organization features
Groups, tagging, and notes for each document.
Pro Helpful support
Staff is helpful in answering questions on how to use the app.
Pro A demo version is available
A time (10hrs) and usage limited demo for Ulysses III is available.
Cons
Con Learning curve is long
While it's better than it used to be, with most functions being possible through the menu, Emacs is still quite a bit different from your standard editor. You'll need to learn new keyboard shortcuts.
Con Sometimes the extensibility can distract you from your actual work
If I ever want to lose half a day, I'll start by tweaking my .spacemacs config file.
Con Keyboard combinations can be confusing for new users
For example, for navigation it uses the b, n, p, l keys. Which for some people may seem strange in the begging. However they can be changed easily.
Con Documentation is not beginner-friendly
Although lots of good built-in documentation _exists_, I have after four years of Emacs as my primary editor not figured out how to actually make use of it, and rely completely on Google / StackOverflow for help.
Con User interface is terrible
I was using Emacs in the early 1980's, before there were GUIs. In fairness to Emacs, its original design was conceived in that context and is rather good at some things, like flexible ability to bind commands to keyboard shortcuts. Unfortunately, it didn't keep up with the times and fails to take advantage of the entire world of GUI design that's revolutionized computer science since then. So Emacs does 5% or what an editor should do quite will, and is surprisingly under-powered and old fashioned at the other 95%. To this day, it lacks or struggles with very basic things, like interactive dialogs, toolbars, tabbed interface, file system navigation, etc., etc. The things I just mentioned, are all present in some limited and inept form, but falls far short of current standard of good user interface design. For this reason, I would not recommend Emacs to anyone who is under 50 year old, or who needs power user capabilities. For casual, unsophisticated applications by someone who grew up with green screen character based computers, it's probably OK.
Con Emacs lisp is very poorly designed
The language that's used for user customization, extensions, and for much of the basic editor functionality, is Emacs lisp, or elisp for short. I actually like lisp in general, especially Scheme, but unfortunately, elisp is one of the worst versions of lisp ever created, barely meriting being called lisp. It's very slow, impoverished in features, inconsistent, and rather inelegant in design. Elisp needed to be overhauled 20 or 30 years ago, but the Emacs developers were not willing to do the work. I believe this is one of the major reasons Emacs is so buggy, lacking in features, development is so slow, and consequently almost nobody uses it (or should use it) anymore.
Con Very poorly maintained
It's not clear to what extent Emacs is still supported. There's still some development taking place, but so slow that it's almost an abandoned project. There are numerous bugs in Emacs, many these days associated with start up and package management. When you search the Internet for solutions, you often find many posts, sometimes going back months or even years, with no clear fix.
Con Hard customization
For customization, you need to learn Lisp.
Con A lot of jokes in this serious software
Con Using Emacs on a new machine without your .emacs file
Con Subscription-based
Ulysses now operates on a subscription-based model. $4.99/month or $39.99/year. It is not currently possible to pay once and keep it.
Con Overwrites imported markdown files
When previously written markdown files are imported, they're converted to Ulysses' version of Markdown and original files are overwritten.
Con Proprietary file format
Text is saved in a database in proprietary format. Meaning, your notes can't be accessed other than through the app, and cannot be moved other than by exporting them.
Con Expensive
Con Cannot render code blocks
You can go around this limitation, but it is complex and not so pretty looking as it is in other Markdown Editors.
Con Lacks a LaTeX-exporter
Con iOS and Mac versions have to be bought separately
The iOS version costs $24.99 and the macOS version costs $44.99. They have to be bought separately in order to be used on those devices.
Con Automatic switching of sheets can be confusing
Scrolling down when at the bottom of a sheet will switch to next sheet. When unexpected, this behavior can be confusing to some.
Con No proper right-to-left support in PDF
Ulysses lacks right-to-left support that was available in the previous incarnation of this software.
Con Proprietary Markdown extensions but no MultiMarkdown
Con Not cross platform
Con Cursor rendering issues
