Meta Platforms’ Muse personal AI agent reached No. 1 on Apple’s U.S. App Store after its Sept. 8, 2026 launch, surpassing ChatGPT in comparable early app-store performance. Sensor Tower data showed more than 2.5 million U.S. downloads, while another report put downloads at 2.8 million in the first 12 days; earlier data cited by Bank of America showed roughly 557,000 daily active users through Sept. 19. Muse can send emails, book travel, complete browser forms and purchases, negotiate, and call businesses to book appointments, check product availability and obtain quotes. The basic plan is free, with subscriptions costing $20 or $100 a month. Meta also tested a human concierge after AI-only calls struggled: human callers achieved 95%-98% success rates in some employee tests, although Meta did not disclose the AI-only rate. The trial was rolled back after a contractor made a racist reference during a cable-bill negotiation. Amazon blocked Muse, alleging unauthorized access and apparent capture of customer credentials, while Shopify partnered with Muse on agentic checkout through Shop Pay. Meta shares rose more than 20% after launch in one later account, while other reports cited different moves and dates. JPMorgan said Muse could become the most widely used consumer AI application since ChatGPT, but adoption, disclosure, privacy, platform cooperation and repeat use remain uncertain.