What is the best way to localize a iOS App project?

You have detailed tutorials describing the process.

Here is one of them: h t t p s : / / w w w.hackingwithswift.com/example-code/uikit/how-to-localize-your-ios-app

1 - Localize everything via my project's main.storyboard 2 - Localize programmatically aka ViewController.swift Approach 1 is much preferable.

A few steps:

1. use NSLocalizing everywhere in code

2. Add languages :

• select project name in navigation panel
• select Project > Info
• select Use Base internationalization
• add languages with the + button

 3. Select storyboard

• In the File inspector, click the languages you want to support
• you will immediately see the change in the File browser panel on the left:

 4. Select Main (english) and translate.

But with that, I'm not sure how to reload a new feature, in case I change sth on the base storyboard.

 5. Now, when you add objects in storyboard, you have to complete those files.

• you can do it using Export / Import localisation from the Product Menu (recommended)
• You can do it another way: add entry manually in the file ; for instance if you add a button, copy a similar entry:

/* Class = "UIButton"; normalTitle = "Go Tab 1"; ObjectID = "40k-P5-pRD"; */
"40k-P5-pRD.normalTitle" = "Go Tab 1";

• And replace what needs to be: ObjectID = "-xx-" in "40k-P5-pRD.normalTitle", as well as the comment
• Adapt the text
• Take care not to remove the semi colon

 6. See tutorial to localize Strings