Swift + Create Main file in Swift
How to Create Main file in Swift Next, File->New->File... to create a Swift file and name it main.swift. Here's how it should look for an iOS app: import UIKit UIApplicationMain ( CommandLine . argc , UnsafeMutableRawPointer ( CommandLine . unsafeArgv ) . bindMemory ( to: UnsafeMutablePointer < Int8 >. self , capacity: Int ( CommandLine . argc )), nil , NSStringFromClass ( AppDelegate . self ) ) NOTE : If we have create custom main.swift file then we don't need to write @UIApplicationMain in appDelegate.swift file