How to detect an iOS App installed or upgraded? [duplicate]

Answer 1

Checkout Swift 3.0 version of code.
Note: Use CFBundleShortVersionString, for checking actual App version checking.

func checkAppUpgrade() {
    let currentVersion = Bundle.main.object(forInfoDictionaryKey:     "CFBundleShortVersionString") as? String
    let versionOfLastRun = UserDefaults.standard.object(forKey: "VersionOfLastRun") as? String

    if versionOfLastRun == nil {
        // First start after installing the app

    } else if versionOfLastRun != currentVersion {
        // App was updated since last run

    } else {
        // nothing changed

    }

    UserDefaults.standard.set(currentVersion, forKey: "VersionOfLastRun")
    UserDefaults.standard.synchronize()
}