Phia is an AI shopping assistant that compares prices across 40,000+ sites — named one of TIME's Best Inventions of 2025. Its core promise: one click tells you if you're getting a good deal.

I evaluated that promise. Using Nielsen's 10 Usability Heuristics across Phia's Chrome extension and web platform, I identified 10 issues — two of which actively eroded user trust. Those two became my redesign focus.