Join me as I chat with Sherry Jiang to discuss her journey creating Peek, an AI-native personal finance app. She explains her development process from rapid prototyping to user testing, and how building in public on social media drove significant user acquisition. The conversation highlights how AI can be leveraged not just within products but also for marketing and content creation.
Timestamps:
• 00:00 – Intro
• 03:58 – Behavioral science principles applied to app design
• 06:13 – AI Chat/Peek for X
• 12:05 – User Testing/Feedback
• 14:00 – Building/Launching App
• 23:04 – Building in Public
• 24:42 – Format for posts
• 35:14 – Content Buckets
• 38:47 – Making Meme’s with ChatGPT
• 47:33 – Final Thoughts
Key Points:
• Sherry Jiang shares how she built Peek, an AI-powered personal finance app that uses behavioral science principles to improve user engagement
• The app was developed through "vibe coding" a prototype in just three hours, followed by user testing with a "rule of six" methodology
• Building in public on Twitter/X was crucial to Peek’s growth, helping it gain thousands of users within a month
• AI tools (Claude, Gemini) were used both for app development and marketing content creation
1) Start with a "Vibe-Coded" Prototype
Sherry built her FIRST version in just 3 HOURS using Next.js!
"You do not have to have something perfect and beautiful on day one" – Sherry
The key? Test with REAL users immediately.
Her "Rule of Six": Talk to 6 people in your target audience.
• Less = not enough data
• More = too slow
2) 4 Behavioral Science Principles That TRANSFORMED Her App
Sherry’s background in behavioral science at Google shaped Peak’s design:
• Show ONE takeaway at a time (no overwhelming dashboards)
• Use conversational UI for personalization
• Create daily "stories" that feel narrative-driven
• Provide actionable next steps, not just data
This is why users open Peak 7X MORE than traditional finance apps!
3) The Dashboard Problem
"Most finance apps feel overwhelming. Lots of numbers and info, but I don’t know what to do with it." – User feedback
The BIGGEST insight: Anxiety comes from seeing problems WITHOUT solutions.
Peak solved this by chunking information and providing clear next steps with every insight.
No more financial anxiety spirals!
4) From Ugly Prototype to Polished Product
Check out this evolution
Sherry took inspiration from:
• Instagram stories for daily financial check-ins
• Wellness apps for card-based UI
• Conversational patterns from messaging
The result? Users say Peak "doesn’t feel as scary as banking apps" and they actually WANT to open it!
5) Building in Public: From 0 to Thousands of Users
Sherry had NO audience when she started.
Her first tweet got just ~500 views.
But she kept showing up CONSISTENTLY with:
• Daily build updates
• 30-day challenges (like "3X retention in 30 days")
• Tech insights
• Finance memes
6) The Tweet-Jacking Hack
Someone tweeted: "I want a finance app with 3 numbers: what I spent today, this week, and this month."
It got 6.5M views.
Sherry replied with her app link + "You also get a cute mascot that roasts you"
She then BUILT that feature OVERNIGHT and tweeted about it.
Downloads exploded!
7) AI-Powered Content Creation
Sherry uses AI to:
• Generate meme ideas based on trends
• Create visuals by iterating on prompts
• Analyze her Twitter to find content angles
Her process: Use GPT to brainstorm ideas → Pick the best one → Refine through multiple iterations
Don’t give up after the first try!
8) The Future of Mobile Apps
"This is the golden age of building AI-native mobile apps." – Sherry
The key insight: We’re moving from static dashboards to dynamic, personalized experiences that understand human psychology.
This isn’t just for finance—this pattern works for ANY app helping people improve their lives.
Notable Quotes:
"This is the golden age of building AI native mobile apps… this is a paradigm shift, not just for personal finance, but for the whole suite of any kind of applications that we’re going to use to improve ourselves." – Sherry Jiang
"You can only do that today in a world where there’s AI and you can ship things overnight." – Greg Isenberg on rapid product iteration
The #1 tool to find startup ideas/trends – https://www.ideabrowser.com
LCA helps Fortune 500s and fast-growing startups build their future – from Warner Music to Fortnite to Dropbox. We turn ‘what if’ into reality with AI, apps, and next-gen products https://latecheckout.agency/
BoringMarketing — Vibe Marketing for Sale: http://boringmarketing.com/
Startup Empire – a membership for builders who want to build cash-flowing businesses https://www.skool.com/startupempire/about
FIND ME ON SOCIAL
X/Twitter: https://twitter.com/gregisenberg
Instagram: https://instagram.com/gregisenberg/
LinkedIn: https://www.linkedin.com/in/gisenberg/
FIND SHERRY ON SOCIAL
Peek Money: https://peek.money
X/Twitter: https://x.com/SherryYanJiang
