I already have a working Google AppSheet inventory application. I need an experienced AppSheet developer to review, test, fix issues, and optimize the existing app. This is not a build-from-scratch project. Current State • App already exists and is connected to a data source (Google Sheets or similar). • Core flows are implemented: items, stock IN/OUT, and basic inventory tracking. • The app is used on iPhone/iPad, with some Mac usage. Scope of Work (What I Need) 1. Functional Review & Testing • Validate that stock counts update correctly in real time. • Confirm transactions (IN/OUT) don’t create duplicates or incorrect totals. • Ensure delivery address tracking works as intended (per transaction or per project, depending on current setup). 2. Performance & Sync Optimization • Reduce sync time and improve responsiveness on mobile. • Clean up schema, formulas, virtual columns, and slices to improve speed. 3. Roles & Permissions • Two roles only: • Admin: full access • User: view + OUT only (no editing items, no IN, no admin tables) • Confirm security filters / slices / actions enforce this correctly (not just UI hiding). 4. UX Improvements • Streamline the “stock OUT” process to be fast and idiot-proof. • Identify friction points and suggest small workflow tweaks that reduce taps and confusion. 5. Alerts • Verify low-stock logic. • Ensure alerts (push/email) trigger reliably under the correct conditions. Out of Scope (Not Included) • Building a brand-new app from scratch • Major redesign or multi-month feature expansions • Complex barcode system beyond AppSheet native scanning (unless clearly recommended as a small add-on) Deliverables • Updated AppSheet app (same project) with fixes and optimizations applied • Short summary of what was changed + why • Quick admin/user guide (PDF or Markdown) Acceptance Criteria • Stock IN/OUT updates totals correctly with no duplication issues • Add/remove stock in under 3 taps (or as close as possible given current structure) • Sync performance meaningfully improved (target: fast on mobile, stable on 4G) • Roles enforced properly (user cannot bypass restrictions) What I Will Provide • App access (AppSheet link) • Access to the connected data source • Test scenarios I care about (warehouse usage) Please include in your proposal: • What you will check first to validate data integrity and stock accuracy • Your approach to improving sync speed in AppSheet • Estimated time to complete an audit + fixes (not a rebuild) Important Clarification This application is not intended for a logistics company or multi-warehouse operation. It is a simple internal inventory control tool for a single company with one warehouse in one physical location. The goal is to track: • What materials come IN • What materials go OUT • Who performed the transaction • Where the material is being sent (job site / delivery address) There is no warehouse-to-warehouse transfer, no complex routing, and no third-party logistics integration. Please keep all recommendations and optimizations aligned with this scope.