XLIFF (XML Localisation Interchange File Format) is the standard file format to pass data from Developers to Translators and between apps.
Xliff is XML-based, which is not friendly for translators who are not good at reading raw xml code. Xliffr supports Xcode-generated xliff files, and helps translators to manipulate xliff files and provides a user-friendly UI to translate in.
Xliffr now supports export xliff file to strings files.
Note: Xliffr does not fully support Xcode 10, currently.