Simple html5 app prototype

I'm looking for an experienced app developer ready to develop a major app. This is a small conceptual prototype meant to test developer capability and technology before moving into full development. The app has the following features: - Register user or login (using e-mail and password) - Create folder (Name) - Invite users to folder (E-mail of user) - Invited users get a invite e-mail with link to download app - Invited users go to create account with e-mail and have access to folder - Invited users and owner of folder can add photos and text objects to folder using app (photo) - All users accessing a folder can see added objects in cronological order - new are highest - A folder has an hashedadress that can be accessed trough the web - this address is available on the folderpage Simple layouts will be provide. The app must be developed using AppGyver Steroids and html5. The appconcept must be tested on iOS and Android. As the app must be very scalable the project and mediastorage must be cloudbased. The developer must recommend and setup a scalable cloudbased storeage.