We are seeking an experienced app developer (mobile or web-based) to create a simple, intuitive tool that helps farmers and agronomists generate fertiliser rate recommendations based on crop type, expected yield, soil and leaf test data, and fertiliser analysis. We will provide a comprehensive spreadsheet containing all relevant nutrient values, crop nutrient removal data, and fertiliser compositions. The developer’s task is to design and build an app that uses these datasets to generate accurate fertiliser rate recommendations. Key Features: User-friendly interface suitable for use in the field (simple menus, large buttons, minimal typing). Input selections: - Crop type (from list provided) - Target yield - Soil test or leaf analysis values (N, P, K, S, etc.) - Fertiliser analysis (select from list or enter manually) Output: Recommended fertiliser rate(s) per hectare Summary of nutrient balance (deficiency or surplus) Option to export or email results as a PDF or CSV Data & Logic: All calculation logic and values will be provided in a structured Excel spreadsheet. The developer will need to integrate this logic into the app so that results are automatically generated based on user inputs. Platform: Open to suggestions, but can be developed as either: A mobile app (iOS/Android), or A web app accessible via browser (desktop, tablet, mobile responsive). Deliverables: Functional app prototype for testing and feedback Final version of app (ready for deployment or publishing) Simple admin panel (optional) for updating fertiliser or crop data in future Skills Required: App development (React Native, Flutter, or equivalent) OR web app development (React, Vue, etc.) Experience integrating Excel-based logic or formulas into apps Good UI/UX design sense (for agricultural field users) Familiarity with agricultural or nutrient management tools is a plus Budget: Please provide a quote and estimated timeframe for: Prototype / MVP Final production version