1. Executive Summary

Zero is the market leader in fasting utility, but it currently operates as a siloed tool. While the biological tracking is world-class, the psychological journey of fasting is unsupported, leading to an "Engagement Leak" where users abandon the app for Reddit or Discord the moment they feel hunger or uncertainty.

This PRD proposes a Community Module designed to transform Zero from a timer into a habit-building destination, increasing Day-30 retention by 25% through real-time peer support and expert-led "Circles."

2. Problem Statement: The "Hour-14" Motivation Gap

Through user research (App Store/Reddit), we identified that the hardest part of fasting isn't the tracking - it's the isolation.

• Isolation at Scale: 60-70% of fasters report irritability and hunger in the first 2 weeks. Without in-app support, 30% drop out within the first month.
• The Engagement Leak: Users leave Zero to ask questions on Reddit (e.g., "Is this headache normal?"), exposing them to unverified "bro-science" and reducing Zero's Daily Active Usage (DAU).
• The Utility Trap: If Zero is just a timer, it is a commodity. Once a user joins an external Discord support group, Zero becomes replaceable by a free stopwatch.

📢 Voice of the User

"I am loving this app... The only thing I’d change is some kind of chat option. I’m new and have questions that experienced fasters may know." — Google User

"I achieve my fasting goals and some of these green circles aren't highlighted... I have no clue what I missed." — Patricia F. (App Store)

"Would anybody like to make a sort of support group? It's easier to get like-minded people who are fasting to ask and answer each other's questions." — Reddit User

3. Market & Competitive Landscape

4. Strategic Objective: "Fast Circles" MVP

The goal is to create "Micro-Communities" based on current fasting status.

4.1 System Architecture & Data Flow