Project sounds interesting and very much of what I have recently done - creating database of entities, applying 2-3 level of filters, data sorting, dealing with ambuigity (resolving conflicts) and all that stuff. While reading you project description I have got at least 6 screens - main screen (navigation/usefull elements to be one-click reachable), list of entities (could be displayed also on main screen as well at least partially), 2nd level list of entities (with similar ones), detailed description of selected entity, list of favorites and settings.
But definetely it will end up with 8-10 screens. So, better to start with UI/UX design, or at least Wireframing. Also, server side - if that's only fetching data from server, storing in the device and processing - that's one thing, if there should be full scope back-end with managing users - that's a bit different.