Report updated May 5, 2026

TL;DR:Zero defends its category lead through a multi-pillar approach that links fasting timers with protein-focused nutrition, but the recent update's technical instability and aggressive paywall shift create a high-churn environment that threatens its #98 grossing position. Users feel Upset, praising core fasting timer and weight tracking tools provide effective health results for long-term users but frustrated by post-update login failures and account access errors prevent users from tracking their fasting progress. Zero maintains a strong position through its protein-tracking differentiator, but the recent technical instability and paywall shift are accelerating churn, so the PM must prioritize authentication stability and restore free-tier value to prevent further rank erosion..|TL;DR:Zero defends its category lead through a multi-pillar approach that links fasting timers with protein-focused nutrition, but the recent update's technical instability and aggressive paywall shift create a high-churn environment that threatens its #98 grossing position. Users feel Upset, praising core fasting timer and weight tracking tools provide effective health results for long-term users but frustrated by post-update login failures and account access errors prevent users from tracking their fasting progress. Zero maintains a strong position through its protein-tracking differentiator, but the recent technical instability and paywall shift are accelerating churn, so the PM must prioritize authentication stability and restore free-tier value to prevent further rank erosion..
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Zero: Fasting & Food Tracker is a struggling health & fitness app that is free with in-app purchases. With a 4.8/5 rating from 445.3K reviews, it struggles with user retention. Users particularly appreciate core fasting timer and weight tracking tools provide effective health results for long-term users, though post-update login failures and account access errors prevent users from tracking their fasting progress remains a common concern.

What is Zero: Fasting & Food Tracker?

Zero is a health and fitness app for intermittent fasting and nutrition tracking on iOS.

Users hire Zero to manage body composition through the combination of fasting windows and protein intake, replacing the manual labor of traditional calorie counting.

Current Momentum

v7.6 · 5d ago

Active
  • Integrated automated Oura data syncing
  • Expanded barcode database for food logging
AI-powered deep analysis surfacing high-signal insights. Still in beta, accuracy improves daily. For informational purposes only.

Active Nemesis

BodyFast: Intermittent Fasting

BodyFast: Intermittent Fasting

By BodyFast

Other Rivals

Lose It! – Calorie Counter
MyFitnessPal: Calorie Counter
Carb Manager—Keto Diet Tracker
Noom Weight Loss, Food Tracker
Oura
Calorie Counter - MyNetDiary
Cal AI - Calorie Tracker

7-Day Rank Pulse 🇺🇸

Health & Fitness

No ranking data

Rating Pulse 🇺🇸

Recent User MoodAI-powered deep analysis surfacing high-signal insights. Still in beta, accuracy improves daily. For informational purposes only.

What makes this app unique?

How Is The App's Momentum Right Now?

Loading...

What Are The Key Features?

Fasting TimerStandard

Real-time tracking with streak monitoring

AI Meal TrackingDifferentiator

Photo-based macro and protein logging

Protein ScoreDifferentiator

Personalized daily targets based on goals

How much does it cost?

Freemium
  • Free version
  • Zero Plus subscription

Freemium model uses a free-to-start entry point with a subscription gate for advanced nutrition and body composition tools.

Who Built It?

Zero Longevity Science, Inc. app icon

Zero Longevity Science

(952)

Helping health-conscious individuals optimize metabolic health and longevity through data-driven fasting and nutrition tracking.

Portfolio

2

Apps

Free 1
Health & Fitness100%

Who is Zero Longevity Science?

Zero Longevity Science has successfully transitioned from a single-purpose utility into a comprehensive metabolic health platform. By expanding their core fasting timer with protein tracking and AI-driven meal logging, they have deepened their moat within the high-intent longevity community. The publisher is currently navigating a strategic shift toward a 'Complete Equation' model, aiming to increase user LTV through mandatory trials and premium AI features despite potential friction in the onboarding flow.

Who is Zero Longevity Science for?

  • Health-conscious individuals
  • Intermittent fasters focused on sustainable weight loss
  • Muscle preservation
  • Metabolic health
Steady

Portfolio momentum

Maintained a steady release cadence with 2 updates in the last 6 months, primarily focused on the flagship title.

Last release · 13d agoActive apps · 1Abandoned · 1

What other apps does Zero Longevity Science make?

What do users think recently?

High confidence · 98 reviews analyzed · Based on 98 reviews. Signal may be noisy.

How did the latest release land?

Overall
4.8/ 5
(445.3K)
Current version
4.8/ 5
0.0 vs overall
(445.3K)
Main signal post-update: core fasting timer and weight tracking tools provide effective health results for long-term users.

What is the recent mood?

Upset

Recent user voice shows a upset sentiment. Users appreciate core fasting timer and weight tracking tools provide effective health results for long-term users, but report post-update login failures and account access errors prevent users from tracking their fasting progress.

What Users Love

Core fasting timer and weight tracking tools provide effective health results for long-term users

What Frustrates Users

Post-update login failures and account access errors prevent users from tracking their fasting progress

What Users Want

Restoration of a functional free tier to allow basic fasting and weight tracking usage

What is the competitive landscape for Zero: Fasting & Food Tracker?

How's The Health & Fitness Market?

How does it evolve in the Health & Fitness market?

Zero holds the #98 Grossing position in the US Health & Fitness category. The recent rank drop of 8 spots indicates that technical instability is impacting monetization velocity.

ChartRankChange
Grossing#93NEW

The rivals identified

The Nemesis

Head to Head

Target must double down on its 'full picture' nutrition integration to differentiate from BodyFast's rigid, coach-led fasting focus.

What sets Zero: Fasting & Food Tracker apart

  • Integrates broader health metrics like protein and hydration tracking to provide a holistic body composition view.

  • Focuses on a more modern, clean interface that prioritizes ease of use for daily habit logging.

What's BodyFast: Intermittent Fasting's Edge

  • Deep library of pre-set fasting schedules reduces the cognitive load for beginners starting their journey.

  • Established community features create a social feedback loop that keeps users engaged within the app ecosystem.

Contenders

Extensive food database with barcode scanning capabilities that significantly reduces the friction of daily logging.

Aggressive release schedule of 29 updates in six months demonstrates rapid iteration and feature responsiveness.

Unmatched food database scale provides near-instant search results for almost any global food item.

Deep integration with hundreds of third-party fitness trackers and wearable devices creates a massive data moat.

Hyper-focused on keto-specific macro tracking, including net carb calculations that general trackers often overlook.

Includes a robust recipe and meal planning engine that provides actionable value beyond simple data entry.

Peers

Uses a curriculum-based approach to change eating habits through daily lessons and psychological reinforcement.

High-touch human coaching model provides a premium service layer that standard trackers lack.

Leverages proprietary ring hardware to provide passive, high-fidelity biometric data without manual user input.

Advanced sleep and readiness scoring provides a context-aware health picture that manual trackers cannot replicate.

Offers a highly polished, ad-free experience that prioritizes user privacy and interface speed.

Includes specialized tracking for diabetes and other medical conditions, expanding its utility beyond general weight loss.

New Kids on the Block

Uses computer vision to identify food items from photos, eliminating the need for manual database searching.

AI-powered calorie estimation reduces the time-to-log for users who find traditional trackers too tedious.

The outtake for Zero: Fasting & Food Tracker

Strengths to defend, gaps to attack

Core Strengths

  • Oura integration increases switching costs via biometric data
  • Protein-focused nutrition logic differentiates from generic calorie trackers

Critical Frictions

  • Login failures post-update disrupt daily habits
  • Premium tier pricing exceeds category median

Growth Levers

  • B2B partnerships with metabolic health clinics
  • Expansion of macro tracking to include fiber and fats

Market Threats

  • Technical instability driving users to BodyFast
  • AI-driven logging in Cal AI reducing manual entry friction

What are the next best moves?

highInvest

Stabilize authentication flow because login failures are the top complaint → restore daily active usage

Login failures and account access errors are the primary drivers of recent negative sentiment.

Trade-off: Pause the new macro-tracking feature development — stability is the prerequisite for retention.

highPivot

Restore free-tier access to basic fasting timers because paywall complaints are driving churn → reduce deletion rate

Aggressive paywall implementation is cited as a primary reason for deleting the application.

Trade-off: Deprioritize the premium-only challenge feature rollout — user base retention is the priority.

A counter-intuitive read

The app's #98 grossing rank is a lagging indicator; the real risk is that the current technical instability is permanently damaging the brand's reputation among long-term, high-value users.

Feature Gaps vs Competitors

  • Real-time coaching plans (available in BodyFast)
  • Extensive barcode database (available in Lose It!)

Key Takeaways

Zero maintains a strong position through its protein-tracking differentiator, but the recent technical instability and paywall shift are accelerating churn, so the PM must prioritize authentication stability and restore free-tier value to prevent further rank erosion.

Where Is It Heading?

Declining

The health tracking market is consolidating around apps that offer low-friction logging and high reliability. Zero's current technical instability and restrictive paywall leave it exposed to competitors like BodyFast, which offer more predictable user experiences.

Login failures post-update prevent users from accessing their data, which directly triggers high-churn behavior and negative reviews.

Aggressive paywall shifts are alienating the long-term user base, leading to a decline in grossing rank as users migrate to competitors.

Disclosure

Independent intel to help builders create better apps.

AI-powered analysis with editorial review, built from publicly available sources. See methodology.

Marlvel.ai is not affiliated with, endorsed by, or sponsored by Zero: Fasting & Food Tracker, its developer, the app publisher, Apple, or Google Play. All trademarks, logos, and screenshots referenced remain the property of their respective owners.

Hope this helps & keep building! · Found an error?

What's new in this report

The app is experiencing a decline in user trust and grossing rank due to post-update technical failures and persistent paywall friction, despite the addition of new biometric integrations.

declined

Sentiment Score Drop

added

Critical Login Failures

removed

Mandatory Trial Tier Removal

declined

Grossing Rank Erosion

added

Biometric Integration

Cite this report

Marlvel.ai. “Zero: Fasting & Food Tracker Intelligence Report.” Updated May 5, 2026. https://marlvel.ai/intel-report/health-fitness/com-courtneycircle-radiant

Agent Markdown (.md)·

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