Localization is feature provided by iOS which translates your app into multiple language.For Localisation,Internationalization is necessary.Internationalization is process of making iOS app able to adapt different culture,language and regions.
Create an individual
Localizable.strings file for each language. The right side would be different for each language. Think of it as a key-value pair:
"str" = "str-language";
Access str in Objective-C:
//Try to provide description on the localized string to be able to create a proper documentation if needed NSString *str = NSLocalizedString(@"string", @"description of the string");
Access str in Swift:
let str = NSLocalizedString("string", comment: "language");