Android inventory application with external scale

We are interested in designing an inventory application for Android tablets. Barcoded samples will be scanned and stored in a specific box. The application will need to record and store box_id, seed_id, inventory_date, weight_gram, and person variables. Collected data should be exportable as a flat csv file or as a MySQL query statement that deletes entries matching the box ids from a database table (seedinv) and reimports the new data. Data should be written and stored to the device memory and recalled upon the app closing. Data should be removed from storage only upon successful export. Exported files should be stored in an “inventory” folder on the memory of the tablet. After the export option is called, the file should be sharable with various web services (e.g. Dropbox). The inventory application should also connect via Bluetooth and, if possible, USB OTG to a scale (API attached). The weight should be constantly displayed and then recorded when input is collected. The developer should be comfortable working with and cleaning up the API so the end user is able to connect devices seamlessly. Scale-related display elements should be hidden unless a scale is connected (although the table can retain the “Wt.” column). A bonus will be awarded if the developer manages to make USB OTG work with the app in addition to the Bluetooth connection. We’re willing to provide any helpful info. The app should match the mockups provided and should function in both portrait and landscape modes with the ability to rotate during data collection without losing data. The app should handle keyboard runtime configuration changes since we will be using an external keyboard to collect data and it may be plugged in and unplugged. Long-pressing entries should display a dialog that allows deletion.