Custom backend Woocommerce Integrated Android App

We need a custom app for android that is integrated with woocommerce store. This is not a customer app, its back end. The app will display orders assigned to user. The user can then scan QR code on certain products and attach to the order and then mark it complete with signature of customer. User can also scan QR code of products being returned with signature. App must have: 1. Login Page : A customer role defined on wordpress can login only 2. QR Scan compatibility 3. Security: See below 4. Hand drawn signature 5. Push Updates: If update is available, don’t let app continue 6. Aesthetics and UI are not important and must be straight forward 7. Compatibility with older Android versions and range of smartphones A very important requirement is that the app must be secure. All calculations and connections must be on server side to protect the code. If you can make this completely on server side in mobile friendly platform, that can be accessed via browser – that will be fine with us as well. Please provide brief description of how you will execute this and a list of projects completed that may be similar.