Landscape universal app background

I’m working on universal game (iPhone and iPad) with SpriteKit and I have issue with background size. I created image size 2048x1536 and more image for iPhone devices in size 1136x852 and still the background is cropped on iPhone. How can I fix it?

let screenHeight = screenSize.size.height

//Backgorund

var dayBackground = SKSpriteNode(imageNamed:"BackgroundDay")
dayBackground.zPosition = -1
dayBackground.position = CGPoint(x:size.width/2, y:size.height/2)
dayBackground.anchorPoint = CGPointMake(0.5, 0.5)
dayBackground.size = self.frame.size

GameViewController:

 if let scene = GameScene(fileNamed:"GameScene") {
    // Configure the view.
    let skView = self.view as! SKView

    skView.showsFPS = true
    skView.showsNodeCount = true

    /* Sprite Kit applies additional optimizations to improve rendering performance */
    skView.ignoresSiblingOrder = true

    /* Set the scale mode to scale to fit the window */
    scene.scaleMode = .AspectFill
    skView.presentScene(scene)
}

iPhone 6 Plus:

In my experience the common cause of this is using a LaunchScreen instead of launch images.

To test this you could duplicate your project and remove the LaunchScreen.