You’ve just finished your latest application. Congrats! Even though you’re only releasing it in English, you’ve used
NSLocalizedString to internationalize your user-facing strings. With strings that require dynamic quantities—“5 items” vs. “1 item”—you handled both the singular and plural cases. You shipped the app and moved on to your next project.
Suddenly your app is a hit… in Russia? You get a lot of feedback that your users want a Russian translation. Easy! You’ll just ship a Russian version of your strings file. Then you realize the problem: in English you can get away with that quick one/not-one check when pluralizing nouns; those are the only two plural categories in the language. Other languages aren’t so simple. Your Russian users have four different rules for pluralizing their nouns. Arabic speakers have six! Thankfully, there are a few tools to help you pluralize nouns for all of them.