REVIEWs

Reviews is a rating and discovery platform built as a Worldcoin Mini App that leverages World ID authentication to create a trusted review ecosystem. Users can search for products by name or scan barcodes (supporting ISBN, UPC, and EAN formats) to instantly access product information and read or write verified reviews. Review solves the problem of fake ratings and bot spam by requiring World ID verification for all review submissions, ensuring each rating comes from a real, unique human. Users can discover products through text search or by scanning physical product barcodes using their phone's camera, making it easy to review items while shopping or at home. Key features include: World ID Authentication: Every review is tied to a verified human identity, eliminating bots and fake accounts Universal Barcode Scanner: Supports ISBN, UPC, and EAN formats with real-time product lookup Product Discovery: Search products by name with instant results and product images Verified Human Reviews: Leave ratings and reviews that other users can trust Mobile-First: Optimized for mobile devices within the World App ecosystem Real-time Product Lookup: Automatic product information retrieval from external APIs Reviews creates a trustworthy source for product opinions where consumers can make informed purchasing decisions based on verified reviews written by authentic humans. Future Possibilities:

• enable editing of reviews
• expanding reviews to include places and venues
• providing shopping and price comparison integrations
• Proof-of-Purchase by leveraging vlayer's web and email proofs

Reviews is built as a Next.js 15 Mini App using the Worldcoin MiniSDK and integrates several key technologies: Frontend Stack: Next.js 15 with TypeScript for the React framework Worldcoin Mini Apps UI Kit for consistent design system compliance Tailwind CSS for responsive styling ZXing library for barcode scanning functionality iconoir-react for consistent iconography Authentication & Identity: Worldcoin MiniSDK (@worldcoin/minikit-js and @worldcoin/minikit-react) for World ID integration Review messages are being signed and saved via a smart contract that also verifies the human verification proof on chain. NextAuth.js v5 for session management World ID verification ensuring each user is a unique, verified human Barcode Scanning Technology: ZXing library for cross-platform barcode detection Support for ISBN, UPC, and EAN format recognition Camera access optimization for mobile devices within MiniSDK constraints Real-time scanning with immediate result feedback Database & APIs: Better-sqlite3 for local product caching and user data for MVP purposes Go-UPC API integration for real-time product information lookup Custom search API endpoints for product discovery Product information caching to reduce API calls and improve performance Notable Technical Implementations: Mobile-first camera integration within MiniSDK constraints, handling device permissions and camera selection (prioritizing back cameras for better barcode scanning) Hybrid search system that checks local database first, then falls back to external APIs for new products Progressive loading states with skeleton components during product lookup Error handling and fallbacks for camera access, API failures, and network issues Optimized bundle size considerations for MiniApp deployment constraints Particularly Hacky/Notable Features: Cross-platform barcode scanning that works reliably within World App's MiniSDK environment Smart camera selection logic that automatically chooses rear cameras for better barcode scanning when available Seamless integration between barcode scanning and World ID authentication for verified product reviews Real-time product enrichment where scanning a barcode immediately fetches product details, images, and allows instant review submission The app successfully bridges physical retail products with digital, verified reviews through the unique combination of barcode scanning and World ID authentication.