I had the same problem when I landed here, turns out I was only using the deprecated application openURL method because i was using google sign in too. To support iOS 8 and before you have to implement both the current and the deprecated method:
func application(_ app: UIApplication, open url: URL, options: [UIApplicationOpenURLOptionsKey : Any] = [:]) -> Bool {
return GIDSignIn.sharedInstance().handle(url, sourceApplication: options[UIApplicationOpenURLOptionsKey.sourceApplication] as! String!, annotation: options[UIApplicationOpenURLOptionsKey.annotation]) || FBSDKApplicationDelegate.sharedInstance().application(app, open: url, sourceApplication: options[UIApplicationOpenURLOptionsKey.sourceApplication] as! String, annotation: options[UIApplicationOpenURLOptionsKey.annotation])
}
func application(_ application: UIApplication, open url: URL, sourceApplication: String?, annotation: Any) -> Bool {
return GIDSignIn.sharedInstance().handle(url, sourceApplication: sourceApplication, annotation: annotation) || FBSDKApplicationDelegate.sharedInstance().application(application, open: url, sourceApplication: sourceApplication, annotation: annotation)
}
The deprecated is the second.
Note: The FBSDK method is added after the google one with an or "||" operator but the order doesn't matter and if you wanna only use facebook method just erase the method and the or operator.
Note 2: As swift 3 still stabilizing the method name can change I suggest you always use the auto complete from XCode when overriding and implementing a delegate's method.
Hope this Helps o/