iOS Facebook SDK open facebook app if installed else browser

I am trying to authorize users via facebook. For now I have what I want and I created custom login button with this code after tap:

[FBSession openActiveSessionWithReadPermissions:permissions
                                   allowLoginUI:YES
                              completionHandler:
 ^(FBSession *session, FBSessionState state, NSError *error) {

     // Call the app delegate's sessionStateChanged:state:error method to handle session state changes
     [self sessionStateChangedForLogin:session state:state error:error];
 }];

It's okay and it's opening browser on facebook login page and after login I have what I need. But I want to login via facebook app if is installed on device. How can I do that? How to change code to check first for installed app and then open browser? Thanks

Solution

You no need to worry . Actually facebook SDK itself first check for the installed Facebook app ,if not available then it will open the browser to enter login credentials.