Phia is an AI-powered personal shopping assistant founded by Phoebe Gates and Sophia Kianni that helps shoppers find the best deal on any item across new and resale markets. Through its iOS app and browser extension, Phia compares prices across thousands of retailers, estimates an item's resale value, and summarizes product details so consumers can decide whether to buy, wait, or buy secondhand. Launched in April 2025, the platform crossed 500,000+ users and signed more than 5,000 brand partnerships within months, positioning itself in the fast-growing agentic and resale-aware commerce space. Phia raised an $8M seed led by Kleiner Perkins followed by a $35M Series A led by Notable Capital, with backing from Khosla Ventures and Kleiner Perkins, valuing the company at roughly $185M.