This is excellent work, a great example of creating a solution to solve a need or want. My only suggestion would be for the addition of an App Preview -
https://developer.apple.com/app-store/app-previews/ - to help users see how the app works live when viewed from the App Store and iTunes. This might help those that are trying to learn how to use it (Cut down the mentioned 2 minutes in one of the reviews to a few seconds).