App developer for fitness app from scratch, regular maintenance needed

I work within the fitness industry and I am currently developing a new style of fitness class. I want to have an app that anyone can view the home page but people/instructors need to pay a monthly fee (can stop anytime) to get past the home page and be able to teach or take part in the class. Their will be 6 classes on the app and every month a new class will be updated replacing an old one so regular app maintenance would be needed. The audio will need to be live streamed so people won't be able to download it. Also I will need this app to be able to play peoples iTunes whilst the audio I have recorded will play over the top. Both the audio and the iTunes on each class page will have a play,pause button and a volume control to ensure the audio can be heard over any music. However the iTunes I am hoping you can either select a playlist through the app (if you have the skills to do this then great) and have skip controls or you can select the playlist before entering the app. links to YouTube tutorial videos on how to teach each class will be needed on each individual classes page. I have a rough architectural idea of what I am wanting but I am happy to take suggestions. On the home page I would like 3 buttons, 1) for accessing class mode. 2)like a link to the promo video 3) option for a shop which will be added at a later date I can go into a lot more detail about the vision I have for this app and how great this can be. How long would it take? Any further suggestions? Willing to pay or offer shares