CardOS is a mobile-first SaaS platform designed specifically for independent trading-card sellers. It integrates multiple functions such as card identification, pricing, inventory management, eBay listing, buyer activity tracking, and sale monitoring into a centralized system. The platform is operational and currently in Version 5, featuring AI-assisted card recognition and eBay connectivity for seller authorization, listing management, and inventory synchronization. CardOS incorporates a durable action queue and customized workflows for inventory, sales, analytics, and seller preferences. The platform has captured feedback from approximately five active beta users and features a user-friendly, dark-mode interface optimized for mobile use while scanning and listing cards. The technology stack includes React, Next.js/Vinext, TypeScript, and more, with full integration with eBay APIs. The platform is live and operational, focusing on product refinement and growth rather than infrastructural redevelopment. Financially, CardOS is pre-revenue, having launched its beta phase in July 2026, with initial operating expenses around $50 for the first month. Several growth opportunities exist, such as introducing paid subscription tiers, expanding pricing intelligence, and establishing partnerships with industry stakeholders. The sale of CardOS includes its custom codebase, brand assets, existing deployed product, and infrastructure configuration, alongside a transitional support period post-sale. It is ideal for buyers with expertise in SaaS growth, collectibles, marketplace tools, or ecommerce software.