If you write a native app programatically, you replace all your localizable strings with NSLocalizedString(@"string to translate", @"message for translator") -

If you write a native app programatically, you replace all your localizable strings with NSLocalizedString(@"string to translate", @"message for translator") - or similar in Swift. There's also support for localizing strings that you supply in your plist config files, which are strings for things like telling a user why you want a certain permission. If you use a lot of Interface Builder (IB), then your localization support stems from all the basic UIKit widgets having support for localization built into IB, and in that case you'll end up building custom components on top of your UIKit blocks, and localizing via IB. One of the views in an app I work on (a Settings view) also uses some plists to generate the table, so we end up having a bit of code to generate the NSLocalizedStrings for the stuff that's not actually in the source code.