How useful is Syntax Control (which Information Architects briefly claimed it was patenting, and would defend strongly, only to change their tune after it was pointed out they were only using Apple technology)? I've never felt the need to see all the nouns or adjectives in anything I've written, and I don't see how it will help me write or edit. Good writing isn't about the number of nouns or proportion of adjectives you use; it's about sentences and how they flow. Syntax Control does nothing useful to that end. The feature also doesn't work that well. In my testing, it missed words, ignored pronouns, and fumbled on words that can be more than one part of speech.
OS X and iOS
Both the OS X and iOS versions of Writer Pro have the same set of features, but I find the iOS version to be a bit confusing. For example, it doesn't show document titles; it shows only the first words of each document. Writer Pro for iOS, like iA Writer, does offer an enhanced keyboard with shortcuts for common punctuation and for document navigation.
I suspect that Writer Pro is one of those love/hate apps. I personally find its features to be unintuitive — and even, at times, confusing — which results in the opposite of iA Writer's elegant simplicity. But I write for a living, so perhaps I have higher standards. For those who write only occasionally, or for school, it might work. What bothers me the most about the app, though, is that in an attempt to impose an artificial workflow on users, the developers have ended up introducing glaring inconsistencies (different fonts in the different modes; forced saving of files in specific folders), and added a questionable feature (syntax control).
If you don't need Writer Pro's workflow modes and syntax control, you could stick to Write mode and use only the app's (still solid) text-editing features, but that would be almost the same as using the less expensive ($5) iA Writer, which is still available. At $20 for each version of Writer Pro, OS X and iOS, it's a pricey risk to try out something you may not like. If there ever was an argument for the need to have demo versions in the Mac App Store and iOS App Store, Writer Pro is it.
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