iOS: Scrivener is one of the best tools for organising your longform writing, but the lack of a mobile app has always been an issue. Today, that's finally remedied with the release of Scrivener for iPhone and iPad. For better and worse, the mobile app is very similar to the desktop app. You get access to all your projects with a familiar set of viewing modes. You can label chapters with colours or icons, access and create notes and do just about everything else you can do with the Mac and Windows apps. Structurally, Scrivener for iOS works the same too, with a binder that's filled with drafts, notes, research and trash. The iOS app also includes most extra features you'd expect to find, including word counts and targets, labelling, a scriptwriting mode and the corkboard view.
Scrivener syncs up with the desktop apps using Dropbox, but you'll need to make sure you update the desktop app before it will work properly. If you've used the desktop app, you know what to expect here, and the iOS version does an admirable job of mimicking the most important features from the desktop apps.
All that said, while the functionality is here, the mobile version is just as ugly and tedious to learn as the desktop apps. Scrivener is jammed full of features and with that comes a ton of complicated menus that take some time to wrap your head around. If looks matter to you, Scrivener's also rather archaic looking, especially when you put it next to an app with more of design-focus, like Ulysses. Still, Scrivener is easily the most powerful tool of its type, and the iOS version does an excellent job of taking the app on the go. It's pricey at $30.99 though, so if you're on the fence on whether it's the tool for you, it's a good idea to check out the demo of the desktop app and watch the feature overview video embedded at the top of this post.
Scrivener ($30.99) [iTunes App Store]