Hydraulic Cylinder Tracker iOS App

I need a dedicated iOS application that lets our shop record and monitor hydraulic-cylinder repairs strictly by serial number. The core workflow is simple: our technicians must be able to scan or type several serial- and model-number pairs in one go, press submit, and instantly see whether each item already lives in the database.

Data rules and behaviour
• Serial numbers must stay unique; duplicates are rejected automatically.
• If a submitted serial already exists, the current warranty date is overwritten with today’s date while the previous date is appended to that cylinder’s Past Repair Dates list. All historical dates have to remain visible, so we can later report how many times a unit was serviced in any given year.
• Each record stores Serial Number, Cylinder Model, Warranty Date (current), and an ever-growing Past Repair Dates array.

User access
Authentication is required, with three distinct roles: Admin, technician, and customer. Admins manage user accounts and can export or purge data; technicians perform the bulk of data entry and edits; customers log in read-only to view the history of their own cylinders.

Platform & tech expectations
The app is iOS-only. I’m open to Swift, SwiftUI, or React Native as long as offline functionality and smooth barcode/QR scanning are possible. A lightweight on-device store (Core Data, SQLite, or Realm) that syncs to a cloud back-end (Firebase, AWS, or similar) will likely make the most sense; feel free to propose alternatives.

Deliverables
1. Xcode project with well-commented source.
2. Simple, intuitive UI for batch entry and history lookup.
3. Role-based login flow.
4. Schema or migration script for the cylinder database.
5. Brief README covering build steps and how to add future roles or fields.

I’ll supply sample CSVs, the current paper form, and any graphic assets once we start. Looking forward to your plan and timeline!