Zero is a metabolic health and fasting tracker for iOS that combines fasting timers with AI-powered meal and protein logging.
Product velocity
Maintenance
Daily rank 🇺🇸
#89
Health & Fitness · grossing
Sentiment
4.8
445k reviews
Nemesis
BodyFast: Intermittent Fasting
The App DNA
What makes this app unique?
Users turn to Zero to replace fragmented health tracking with a unified dashboard that connects fasting intervals with nutritional outcomes, removing the friction of manual calorie counting.
For Individuals focused on weight loss, muscle retention, and metabolic health who prefer automated tracking over manual calorie counting.
Key features
Configurable fasting intervals with real-time progress tracking and streak monitoring.
Photo-based food logging that automatically calculates macros, protein, and calorie content.
Personalized daily protein target calculation based on user weight and health goals.
How much does it cost?
The freemium model gates advanced nutrition metrics and AI logging behind a subscription, which users report as overly restrictive.
Velocity
Maintenance developmentUX improvementsperformanceShow more...
The app maintains a slow release cadence, shipping approximately 0.08 releases per week. The latest release focused on minor refinements to goals, barcode coverage, and syncing, following a period of stability improvements. Development activity is currently limited to maintenance and minor functional adjustments rather than significant feature expansion. The last update occurred 91 days ago, reflecting a stable but low-frequency development cycle.
Who built it?
Zero Longevity Science
3 apps tracked · Health & Fitness
Zero - Intermittent Fasting
Less - Alcohol TrackerUser Sentiment
What do users think recently?
The recent review mood reads upset. Users appreciate manual fasting and weight tracking tools provide a simple and effective health monitoring experience and integration with health platforms like fitbit and apple health allows for convenient centralized data management, but report aggressive paywalls prevent new users from accessing basic app functionality without a paid subscription.
How are ratings & reviews evolving?
What users say, by theme
- Manual fasting and weight tracking tools provide a simple and effective health monitoring experience
- Integration with health platforms like Fitbit and Apple Health allows for convenient centralized data management
- Aggressive paywalls prevent new users from accessing basic app functionality without a paid subscription
61 of 98 recent reviews analyzed · high confidence · Upset overall
Read the full review analysisUnlock 2 more frustration themes and 1 user request, each backed by review evidence.
Access the full report for freeCompetition
Competitive landscape for Zero: Fasting & Food Tracker
How's the Health & Fitness market?
Zero holds a #93 Grossing position in the US Health & Fitness category. The recent decline in grossing ranks across international markets suggests the current subscription-only model is creating friction that outweighs the app's discovery advantage.
Read the market outlookThe rivals identified
By BodyFast GmbH
Direct thematic overlap in intermittent fasting tracking with a massive, established user base and consistent release cadence.
- Offers highly structured, coach-led fasting plans that guide users through specific protocols daily.
- Provides a dedicated fasting-focused community experience that encourages long-term adherence through social accountability.
- Monetization model relies heavily on premium coaching plans rather than just basic tracking features.
Carb Manager—Keto Diet TrackerContender
MyFitnessPal: Calorie CounterContender
Calorie Counter by Lose It!ContenderUnlock the head-to-head verdict: where this rival wins, and where it loses.
Access the full report for freeThe Analyst's Read
Key takeaways for Zero: Fasting & Food Tracker
Where is it heading?
The metabolic health market is consolidating around low-friction, AI-driven logging, leaving Zero's subscription-only model increasingly exposed. Without a functional free tier to anchor the user base, Zero risks losing its market position to rivals that prioritize accessibility and technical reliability over aggressive monetization.
- Technical instability post-update (login failures, data loss) erodes trust, which compounds the sentiment drag from the restrictive subscription-only model.
- Grossing rank volatility across international markets suggests the current pricing model is failing to sustain the user funnel against ad-supported rivals.
The SWOT
- Proprietary Protein Score metric increases user reliance on the app for daily nutrition guidance.
- Automated Oura syncing integrates biometric data to increase platform stickiness.
- Localized pricing could capture high-ARPU markets where the current subscription-only model is driving churn.
- Expanding the free tier to include basic calorie tracking could reduce the current high-friction onboarding barrier.
Next best moves
Restore account reliability because login failures and data loss are the #1 churn risk → stabilize long-term retention
+ 1 more prioritized moveThe counter-intuitive read
Zero's restrictive paywall is not just a monetization error…
Read the full takeFeature gaps
Barcode scanning (available in Lose It! but missing or limited here) +1
Since the last report: The app has transitioned to a maintenance-only development cycle while simultaneously tightening its subscription-only paywall, which has exacerbated user churn and failed to resolve persistent technical instability.
Bottom line
Restoring account stability and softening the paywall to allow basic utility are essential to reversing the current sentiment decline. Prioritizing these foundational fixes will unlock the retention needed to compete against high-velocity calorie trackers.
Unlock 2 critical frictions, 2 market threats, 1 more prioritized move and the analyst’s take.
Access the full report for freeSources
- [1] App Store, source
Report last updated