A magnifying glass effect view to show on top of screen content as seen in this video: https://www.youtube.com/watch?v=MppiS0iD3qY

MagnifyingView.swift

public class MagnifyingView: UIView {
    private weak var viewToMagnify: UIView!
    private var touchPoint: CGPoint!
    var zoomScale: CGFloat = 2

    public required init?(coder aDecoder: NSCoder) { fatalError() }

    public init(viewToMagnify: UIView, size: CGSize) {
        self.viewToMagnify = viewToMagnify
        super.init(frame: CGRect(origin: .zero, size: size))
        setup()
    }

    private func setup() {
        self.layer.borderColor = UIColor.lightGray.cgColor
        self.layer.borderWidth = 3
        self.layer.cornerRadius = bounds.size.height
        self.layer.masksToBounds = true
    }

    public func setTouchPoint(_ point: CGPoint) {
        touchPoint = point
        self.center = CGPoint(x: point.x, y: point.y)
        setNeedsDisplay()
    }

    public override func draw(_ rect: CGRect) {
        guard let context = UIGraphicsGetCurrentContext() else { return }
        context.translateBy(x: self.frame.size.width * 0.5, y: self.frame.size.height * 0.5)
        context.scaleBy(x: zoomScale, y: zoomScale)
        context.translateBy(x: -touchPoint.x, y: -touchPoint.y)
        self.viewToMagnify.layer.render(in: context)
    }
}