A replication of download button in the App Store.

OfferButton.swift

import UIKit

class OfferButton: UIButton {
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        setup()
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        setup()
    }
    
    private func setup() {
        self.layer.cornerRadius = 14
        self.layer.masksToBounds = true
        
        self.setTitleColor(self.tintColor, for: .normal)
        self.titleLabel?.font = .systemFont(ofSize: 15, weight: .bold)
        
        self.setBackgroundColor(.tertiarySystemGroupedBackground, for: .normal)
    }
    
    override var intrinsicContentSize: CGSize {
        return CGSize(width: 72, height: 28)
    }
}