I'm looking into push notifications for an app I'm creating. I've heard lots about UrbanAirship but I can't seem to find a definitive reason why I should use it? As far as I understand it UA is a middle man? This page shows the free version doesn't have a push composer, so a developer will still need a server themselves to create the notification, if their own server is needed then I might as well go directly to APNS?
What is the point and advantage of UA? And if you use it how do you send notifications without your own server?