She Built an AI App Alone in 60 Days

How Selina Li did it: She Built an AI App Alone in 60 Days

Selina Li is the founder of gymii.ai, "an AI powered consumer app" with the goal of making nutrition tracking easy and social. Instead of manually logging food, users take a photo or snap a video of a meal and gymii's AI breaks it down into dishes, ingredients, calories, macronutrients and micronutrients. The second half of the idea is community: users can share their meals, see what friends are eating, like and comment, and share their journey — the part Selina felt was missing from a nutrition experience she found isolating.

The catalyst was personal. Selina has been a competitive golfer for 16 years, playing from the age of seven through college, so nutrition always mattered for performance and well-being. She'd tried tracking with apps like MyFitnessPal but found it "such a cumbersome experience" she couldn't stick with it. Meanwhile she loved the social, shareable feel of fitness tools — her Apple Watch, watching friends' trails on Strava — and wanted to bring that energy to a space she felt was usually treated as "so annoying to do." gymii is deliberately designed to be a "safe type of social space": users control exactly who they share with, right down to a single accountability friend, and can post zero meals if they want. The team surveyed more than 400 people and found 82% wanted to share their nutrition journey.

What's striking is how Selina built it. Before onboarding her CTO Zach, she wrote almost every line of code — despite, as Thea points out, coming to her for help on coding homework in college. Her advice to non-technical founders: large language models are "super intelligence at your fingertips for like 20 bucks a month," roughly "three cups of coffee in New York." She "basically built it in two months, the MVP in two months, with no prior full stack experience," leaning on tools like V0 for front-end design mockups. She's now doing a master's in computer science to build a stronger technical foundation, but her message is simpler: "just find a project and go for it."

On funding, Selina spoke to VCs for the first few months and kept hearing they weren't looking hard at consumer right now. Once she understood that consumer customers are "really unpredictable" and that VCs want "a very clean path to profitability," it actually cleared her head: rather than asking "how can I please these investors," she went back to building "a product that users genuinely love." So gymii is bootstrapping — cheaply, because the MVP took two months, launch came within roughly six months, and back-end costs for hosting and vision language models were "a fraction" of what she expected.

By the time the episode aired, gymii had launched on the App Store in early February and would be live on the App Store and Google Play Store. After roughly four months of searching for a co-founder, two months of trial on gymii, and a stint as a solo founder until December, the team is now heads-down on a different muscle entirely: marketing, social media, micro-influencer partnerships, and getting the app into the hands of strangers beyond the 100-plus beta testers.

What you'll hear

• What gymii actually is — snap a photo or video of a meal and the AI breaks it into dishes, ingredients, calories, macros and micros
• Making nutrition social and safe — full control over who you share with, down to a single accountability friend, validated by a 400-person survey
• Building with no full stack experience — how Selina wrote almost every line of code and shipped the MVP in two months
• Why she stopped chasing VCs — what she learned about consumer vs. B2B and why bootstrapping gave her a cleaner mindset
• Finding a co-founder through a trial period — four months of searching and the dynamic that convinced her about Zach
• The solo-founder loneliness — the stark contrast from a sports team and corporate to being "completely alone in the journey"
• The flip side of the founder journey — moving from in-the-weeds engineering to marketing and putting yourself out there

Key claims from this episode

Chapters

Quotes from this episode

Themes Selina returns to

• Easy and social — making nutrition tracking seamless and shareable, the opposite of a chore
• A safe social space — designing community so users control exactly who sees what, down to one friend
• Inclusive, not weight-obsessed — supporting weight goals but also people who just want to feel better
• AI as a partner in crime — leaning on LLMs and tools so a non-technical founder can build a real product
• Build for users, not investors — why bootstrapping gave her a cleaner mindset than pleasing VCs
• A co-founder as check and balance — the value of trial periods, complementary strengths and friendly disagreement