Building a Multimodal Game-Box Scanner with VisionKit, IGDB, and GPT-5.6 Luna

Duo Queue, an iOS app for two-player game nights, now uses a multimodal scanner combining VisionKit, IGDB, and GPT-5.6 Luna to identify Japanese game boxes, achieving 43 of 44 correct identifications in tests. The scanner initially failed on Japanese text, misreading Pokémon Red as "New Trestar" and finding no results for Japanese titles. A 452-line dictionary and cover-art fingerprinting improved accuracy, but the addition of GPT-5.6 Luna to correct OCR errors proved decisive, boosting success from 27 to 43 of 44 test strings. The app sends a 640px JPEG to the server, with OCR as a hint, taking about 6.5 seconds per scan. Version 1.1 went to App Review on September 22, 2026, after six days of development.