AppDelegate.swift

import UIKit
import StreamChatClient

...
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.
        Client.configureShared(.init(apiKey: "31e2eqp53qu3", logOptions: .info))
        return true
    }
...