UIDeviceExtention.swift

// 1. Declare outside class definition (or in its own file).
// 2. UIKit must be included in file where this code is added.
// 3. Extends UIDevice class, thus is available anywhere in app.
//
// Usage example:
//
//    if UIDevice().type == .simulator {
//       print("You're running on the simulator... boring!")
//    } else {
//       print("Wow! Running on a \(UIDevice().type.rawValue)")
//    }

public enum Model : String {
    case simulator = "simulator/sandbox",
    iPod1          = "iPod 1",
    iPod2          = "iPod 2",
    iPod3          = "iPod 3",
    iPod4          = "iPod 4",
    iPod5          = "iPod 5",
    iPad2          = "iPad 2",
    iPad3          = "iPad 3",
    iPad4          = "iPad 4",
    iPhone4        = "iPhone 4",
    iPhone4S       = "iPhone 4S",
    iPhone5        = "iPhone 5",
    iPhone5S       = "iPhone 5S",
    iPhone5C       = "iPhone 5C",
    iPadMini1      = "iPad Mini 1",
    iPadMini2      = "iPad Mini 2",
    iPadMini3      = "iPad Mini 3",
    iPadAir1       = "iPad Air 1",
    iPadAir2       = "iPad Air 2",
    iPhone6        = "iPhone 6",
    iPhone6plus    = "iPhone 6 Plus",
    iPhone6S       = "iPhone 6S",
    iPhone6Splus   = "iPhone 6S Plus",
    unrecognized   = "?unrecognized?"
}

public extension UIDevice {
    public var type: Model {
        var systemInfo = utsname()
        uname(&systemInfo)
        let modelCode = withUnsafePointer(to: &systemInfo.machine) {
            $0.withMemoryRebound(to: CChar.self, capacity: 1) {
                ptr in String.init(validatingUTF8: ptr)

            }
        }
        var modelMap : [ String : Model ] = [
            "i386"      : .simulator,
            "x86_64"    : .simulator,
            "iPod1,1"   : .iPod1,
            "iPod2,1"   : .iPod2,
            "iPod3,1"   : .iPod3,
            "iPod4,1"   : .iPod4,
            "iPod5,1"   : .iPod5,
            "iPad2,1"   : .iPad2,
            "iPad2,2"   : .iPad2,
            "iPad2,3"   : .iPad2,
            "iPad2,4"   : .iPad2,
            "iPad2,5"   : .iPadMini1,
            "iPad2,6"   : .iPadMini1,
            "iPad2,7"   : .iPadMini1,
            "iPhone3,1" : .iPhone4,
            "iPhone3,2" : .iPhone4,
            "iPhone3,3" : .iPhone4,
            "iPhone4,1" : .iPhone4S,
            "iPhone5,1" : .iPhone5,
            "iPhone5,2" : .iPhone5,
            "iPhone5,3" : .iPhone5C,
            "iPhone5,4" : .iPhone5C,
            "iPad3,1"   : .iPad3,
            "iPad3,2"   : .iPad3,
            "iPad3,3"   : .iPad3,
            "iPad3,4"   : .iPad4,
            "iPad3,5"   : .iPad4,
            "iPad3,6"   : .iPad4,
            "iPhone6,1" : .iPhone5S,
            "iPhone6,2" : .iPhone5S,
            "iPad4,1"   : .iPadAir1,
            "iPad4,2"   : .iPadAir2,
            "iPad4,4"   : .iPadMini2,
            "iPad4,5"   : .iPadMini2,
            "iPad4,6"   : .iPadMini2,
            "iPad4,7"   : .iPadMini3,
            "iPad4,8"   : .iPadMini3,
            "iPad4,9"   : .iPadMini3,
            "iPhone7,1" : .iPhone6plus,
            "iPhone7,2" : .iPhone6,
            "iPhone8,1" : .iPhone6S,
            "iPhone8,2" : .iPhone6Splus
        ]

        if let model = modelMap[String.fromCString(modelCode!)!] {
            return model
        }
        return Model.unrecognized
    }
}