In an ideal world, the possibility of future internationalization should be on our mind every time we set up a new Xcode project. In the real world, it very rarely is. Localization is often an after thought and the further we go through an app's development and the more strings we add to our .m class files, the more likely we are to be put off by what seems such a massive undertaking.
Mac OS X allows you to take a screenshot without interrupting your workflow. There is also some area flexibility when taking a screenshot.
Developers and translators often need to test their localizations before approving them.
It is important to preserve text encodings when sending, receiving and editing files. Default text encodings differ from machine to machine, but fortunately there are a list of standard, common encodings which every good text editing tool should offer.
If you installed the Command Line Utilities along with Xcode (by default, you did) then you can use IBTOOL to extract strings from your XIB files. The process is simple and very manual. It may be better to consider using a 3rd party tool to help you.
iOS allows you to take a screenshot without interrupting your workflow while using your iPhone, iPad or iPod touch.