Android Developer - Online purchasing app

Basic guidelines: - The app must be intuitive and look modern. - We already have the logo and trademark. Front-end draft: The app will work as an online purchase store. Our products will be 100% virtual, so no stock management nor shipment are required. The user must be able to navigate through our store, filter the results and purchase any item, which will be then stored on their profile. Once the user buys an item he/she will have permanent access to it. Furthermore, the user must be able to rate and write reviews on the purchased items, as well as share outside the app (whatsapp, facebook, etc.). All users have profiles. If the user decided to keep his/her profile public, he/she can be followed by anyone (just like instagram, for instance). Actions made by the users a user follows will appear on the Feed (see below). The user profile will contain basic info such as Name, Gender, Age, Birth Country, etc. as well as the number of followers/following. The ability to communicate in a minimalist way using the app (direct messages between users) could be considered too. The app should have a single main fragment, whose content would be changed according to the selected entries of a lateral menu. The lateral menus should contain the following entries: - Feed: This would be the main page showed once the app is started. The actions and purchased items of those users you follow would appear here. Also new offers could appear here too. - Offers: This fragment would display a simple list with all offers (products) available to purchase. A filter mechanism must be implemented here to allow the user to sort & filter among all products categories. Each product preview must be accessible. - My products: A list showing all purchased items. Once a product has been purchased the user gets the ability to review and rate it. Each product can be visualized in here too (see its description and all details). - On action: Our products are 100% virtual. This means that "consuming" our products can occur at any time, any place and as many times as desired. Each one of our products comes with different experiences, and using these experiences online requires things such as GPS location, Route optimization, audiovisual media capture, storage and reproduction, among others. This fragment (ON ACTION) allows the user to "use" a certain purchased item. As an example, with a totally different product type, let's IMAGINE the app we are proposing sold cooking recipes: the user would buy a specific recipe, then he/she could navigate the full recipe item on the on action fragment, where the ingredient list would appear, along with some videos tutorials, and some ability to take pictures of the final result (which could appear on the Feed fragment, mentioned before). These are the main guidelines the developer should follow to implement all required functionalities.