Thanks again for your comments. I was able to successfully send a push notification through the Ionic.io dashboard today, tomorrow I will try your $http.post function and see if that works.
Regarding reading through the app's source code—if the github repo is private and because the app is complied to a native build for iOS and released through the App Store, how would a person get to the source code? It's not the same as a web browser where a person can open their console and inspector and see all of the code on the client.
This makes me think that perhaps an intermediary server is overkill for a developer who is making an app for a smaller audience.
Would love your thoughts.