you can use this:
try {
Intent followIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("fb://facewebmodal/f?href=" +
"https://www.facebook.com/app_scoped_user_id/"+scoped user id+"/"));
activity.startActivity(followIntent);
} catch (Exception e) {
activity.startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("https://www.facebook.com/" + user name)));
String errorMessage = (e.getMessage() == null) ? "Message is empty" : e.getMessage();
}
attention: you can get scoped user id from "link" permission facebook api