When? sideWhen founders Phoebe Gates and Sofia Kiani decided to create an AI startup, they targeted an area they understood well: online shopping.
The founders, who met at Stanford when they were randomly paired as roommates, understood e-commerce as they spent hours trying to find the right items to expand their wardrobes. And they realized that AI has the potential to help people discover, shop, and buy in new ways. They also realized that the potential was a market opportunity.
“There felt like there was this huge white space, like, what should we actually buy, and why doesn’t everyone have a personal shopper in their pocket?” Gates said on stage at TechCrunch Disrupt 2025 on Tuesday.
The startup emerged from a class project where it proved its initial demand. But the service didn’t launch to the public until Fia found the right product-market fit, Kiani says.
This tool is available as a browser extension ApplicationAllows buyers to compare prices, including on second-hand items, adding a sustainability factor to the shopping experience.
Fia says it integrates with more than 150 second-hand platforms, and has more than 350 million items in its in-house search database. Kiani said that buying second-hand reduces the carbon footprint by 80% compared to buying new. Plus, it’s cheap.

Kiani said the service also helps users understand what they are purchasing. “If you’re looking at a $500 handbag on Fia, you can quickly figure out, can you resell that item for $300 or $400? Or, conversely, if it’s a fast-fashion piece and you’re buying it for $100 bucks, is it only reselling for $10? Does it depreciate immediately and lose 90% of its value?”
The startup is also developing an AI shopping advisor that will help users understand price factors like a good deal, or what an item’s retained value might be, as well as fashion basics like whether the item will fit based on the user’s previous orders and returns. The founders said the Sizing Insights feature is currently in beta with a small group of users.
Founders have used a variety of tactics to attract audiences, including an ambassador program, creating their own content about the product’s development, and even starting a podcast.
“The ability to get hundreds of thousands of downloads at a very low cost through podcasts and different distribution vehicles has been really important,” Kiani said.
Plus, Gates said, sharing the realities of building a startup with his audience helped Fia’s potential users connect with the founders and their story.
“I think there was some ego death that we had to go through,” Gates said. “At first, it’s like, ‘I want to look good in all my content.’ But if you want people to engage, and you want to create the amount of content that we need, you just have to be able to pull back the curtain.
Gates, whose father is yes, that gatesAcknowledges that she came to the startup experience from a position of privilege, but says they don’t necessarily turn to her for advice.
“So, while my dad — I think he’s a genius — he’s not the guy shopping on Fia, okay? Like, he’s not looking for the best deal on different sites. He’s not comparing items on his wish list for his spring break trip,” she said.

