REST API for IOS

What is the simplest way to get the data in iOS application in SWIFT? I can not understand how to use the REST API http://swagger.io/.

Can anyone help me show me a starting point?

You can look at the official Traccar Manager app. It's written in Swift and it's using the API to communicate with server side.

I've looked and I was not able to fully understand.

What I am trying to make is this, that in javascript.

But I not yet found a way to pass this to Swift.

// find All devices  - GET request
var result = HTTP.call(
    "GET",
    'http://your_domain:8082/api/devices/',
    {
        auth: 'email@xyz.com:password' ,
        params: {
        }
    }
);

What are you talking about? Traccar Manager is written in Swift language, it's not in JavaScript.