UIApplication extensions. Bundle marketing and build versions

UIApplication+Extensions.swift

extension UIApplication {
    static var appVersion: String? {
        return Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as? String
    }

    static var buildVersion: String? {
        return Bundle.main.object(forInfoDictionaryKey: "CFBundleVersion") as? String
    }

    static var fullVersion: String? {
        guard
            let marketingVersion = appVersion,
            let buildNumber = buildVersion else {
            return nil
        }

        return "\(marketingVersion)(\(buildNumber))"
    }
}