Will, your push notification comes from the actual browser on your phone...

It will work when you allow for push notifications from the site.

Note: it will not work with an iPhone (on Safari)...that's just because Apple is Apple and it's on their end...I've had mixed results with Chrome on Iphone as I personally can't get it to send me a notification and haven't had anybody else be able to get them also...

If you're using Chrome or Firefox for your browsers the push notifications will work if you set up your OneSignal correctly...