iOS/Android app For Reading Serial Numbers, Taking Photos, Entering Inventory Information

We require an app that will essentially have 4 main pages: Login, Landing Page, Inventory Entry Page, Photo Page and 2 Services: Serial Number Reader, Take Photos. Backend login, database, and API work is NOT included in this project. Assume all database interactions are via API. Page by page breakdown: 1.) Login Screen: User credentials entered and verified 2.) Landing Page: User starts here after login. They will be able to see previously entered inventory and either select one of those, or enter new inventory 3.) Inventory Entry Page: From this page, User will be able to either: a.) Use Serial Number Reader To populate inventory information. Serial Number posted to API, details sent back in the response that is loaded on the page. b.) Manually enter information via drop down's and text boxes. Drop downs are multi-level, so the selected value in one, will cause the next one to reload its available options. After Inventory Entry Page, inventory is posted and saved, then user can either return to Landing Page, or proceed to take photos. 4.) From Photos Page, User can review/delete previously taken photos or take additional/new photos. Services: 1.) App should be able to read serial/decipher serial number. Serial number then posted to API to retrieve inventory details. 2.) App should also be able to take photo that will be posted to API and associated with specific inventory. Branding is ongoing, so might require some additional touch-ups at a future date. These should be minor.