Last year, I reviewed Ulysses III for OS X, explaining that it "is much more than just a Markdown editor [...] as it includes a good number of organizational features." Since then, The Soulmen, the app's developer, has updated the OS X app to version 2, and introduced an iPad app. The $20 Ulysses for iPad attempts to reproduce the OS X experience — interface and features — on an iPad, and does so quite well.
I prefer using apps that have both iOS and OS X versions: I find it makes my computing experience smoother if I shift between devices. If you feel that way, you know that the iOS version of your favorite app can't be an exact copy of the OS X version, but you want it to be as close as possible. The Soulmen previously released an iPhone app called Daedalus Touch, which offers some compatibility with Ulysses, but does so in a confusing manner. Ulysses for iPad, however, is nearly a mirror image of the OS X app, allowing you to smoothly switch from one to the other.
Like the OS X version, Ulysses for iPad displays Markdown syntax in what some people find a more user-friendly manner, coloring different types of text, and displaying links, images, and footnotes behind tokens. (You may like or dislike this, depending on how you are used to working with Markdown.)
When I say you can switch smoothly, I only mean as far as the interface is concerned. Ulysses syncs your files via iCloud, and you can't just start writing on a Mac and switch to an iPad; you need to wait for iCloud to update your file. This isn't Handoff, where you can truly switch from one document to another across devices (assuming Handoff works with your hardware); this is iCloud's "Will it sync?" syncing, the kind that sometimes takes several minutes or more. Unfortunately, iCloud sync conflicts are common, and there is a complicated procedure to get the apps back in sync. I've lost data too many times with apps that use iCloud to be comfortable with trusting my files to it.
When your files do sync, you'l find that the iPad version of Ulysses is nearly exactly the same as the OS X version. This is no mean feat. Ulysses for iPad starts by reproducing your file organization; at least for files on iCloud (you can store files on your Mac with the OS X version and they won't show up on the iPad). You can create folders — what Ulysses calls Groups — that appear in both versions of the app and organize your files as you want. You may want to keep a library of files accessible, along with documents you're currently writing, and Ulysses lets you do that efficiently.
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