Comparison

Zero vs Zero Fast

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Zero

This app tracks intermittent fasting and nutrition to help users achieve real body composition changes. It integrates fasting, protein intake, meals, hydration, and habits for a holistic approach to weight loss and metabolic health.

Highlights
  • Intermittent fasting timers and streaks
  • Smart meal logging with photo recognition
  • Personalized daily protein target tracking
  • Integrated fasting and protein tracking
  • Water and habit tracking
  • Science-based insights on fasting and nutrition
Features
Read full description

Zero is the all-in-one fasting tracker and nutrition app built for real results. Most fasting and weight loss apps stop at simply tracking fasts or calories. Zero connects the full picture — fasting, protein, meals, hydration, and habits — so you actually change your body composition, not just your eating schedule. Here’s how Zero helps you get there: • Track your intermittent fasting — Engage timers, streaks, and insights keep you stay motivated and consistent across your entire fasting journey. • Log meals the smart way — Skip the tedious manual meal entry routine. With Zero Plus, snap a photo and get instant macros, protein composition, and clarity on how effectively your meals support your goals. Your first meal logs are on us, so you can try it before you subscribe. • Hit your Protein Score — Zero Plus tracks a personalized daily protein target that adapts to your weight and goals. Better protein = better satiety, better muscle retention, better weight loss. Zero makes it automatic. • Complete the equation: Fasting + Protein — Most people fast or track meals. Zero brings them together so you lose weight, protect muscle, and avoid the pressure and guilt of traditional calorie trackers. • Stay hydrated to power your fasts — Water tracking with Zero Plus helps you maintain energy, reduce cravings, and support metabolic function throughout the day. • Build healthy habits that actually matter — Track movement, sleep, mood, and other daily pillars that reinforce your fasting and fueling routine. • Challenge yourself — Hit protein targets, maintain fasting streaks, and stay accountable with motivating challenges built around outcomes, not vanity metrics. • Learn the real science — Understand how fasting, protein, and hydration work together for sustainable weight loss and metabolic health — with insights from leading experts. • See measurable progress — Watch your streaks grow, your protein consistency rise, and your body composition improve with clean, insightful trend views. Whether you’re starting out or optimizing an existing routine, Zero gives you the structure, guidance, and clarity most apps miss. Zero is not a medical device and does not provide medical advice, diagnosis, or treatment. Always consult your doctor or qualified healthcare provider before making any changes to your diet, fasting routine, or health regimen. Zero is free to download, with fasting timers, streaks, weekly trends, expert articles, and challenges included. Zero Plus is an optional subscription that unlocks photo meal logging and your Protein Score, water tracking, custom fasts and saved presets, Fat-Burning Mode, the mood journal and daily habit insights, premium articles and Plus-only challenges, and monthly, yearly, and correlated charts. A free trial is available. Payment for Zero Plus will be charged to your Apple Account when you subscribe. Subscriptions automatically renew unless auto-renew is turned off at least 24 hours before the end of the current period. Manage your subscription in your Account Settings. Read more terms & conditions: Terms of use: https://www.zerolongevity.com/terms-of-use Privacy policy: https://www.zerolongevity.com/privacy-policy

About

Zero Fast

This app guides you through intermittent fasting, indicating when your body enters fat-burning and ketosis. It offers group challenges for motivation without requiring calorie counting or strict diets.

Highlights
  • Intermittent fasting timer
  • Fat-burning and ketosis indicators
  • Group fasting challenges
  • No calorie counting
  • Meal planner integration
Features
Read full description

Your fast, explained as it happens. Zero Fast times your fast, shows you the moment your body switches to fat-burning and ketosis, and lets you race friends in group challenges. No calorie counting. No strict diets.

Screenshots

Zero4 screens
Zero Fast4 screens

Verdict

The call

Zero and Zero Fast both sit at 4.8 stars, but that hides the real split: 100% of Zero Fast's written reviews are positive against 32% of Zero's. Zero's advantage is ratings volume (445K vs 1) and chart position (#119 vs unranked). On price, rating, update cadence and ads there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Zero sells 10 in-app purchases, starting at $9.99 per month and Zero Fast sells 2 in-app purchases, starting at $3.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Zero Fast holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: Zero has 445K ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 32% of Zero's written reviews are positive against 100% of Zero Fast's.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 2 weeks. The most recent releases landed on October 31, 2026 and October 30, 2026 respectively.

Scorecard4 real differences · 7 level
Zero versus Zero Fast: the parameters behind the verdict, then further details
ParameterZeroZero Fast
PriceFreeFree
Rating4.8 (445K ratings)5.0 (1 ratings) — better
Positive reviews32.2% of reviews100.0% of reviews — better
Number of ratings445K — better1
Update frequencyEvery 2 weeksEvery 2 weeks
AdsNoNo
In-app purchasesYesYes
MonetizationFreemiumFree with in-app purchases
Best chart rank#119 — better—
DevicesiPhone, Apple WatchiPhone, iPad
Requires iOS17.0 — better26.0
Further details — not scored
Size195 MB41 MB
Age rating17+12+
DeveloperZero Longevity Science, Inc.APPE LATTE LIMITED

Customer experience

Zero

All ratings445,285 ratings
Positive96.3%
Neutral2.1%
Negative1.6%
Written reviews1,393 reviews
Positive32.2%
Neutral8.5%
Negative59.3%

Zero Fast

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Zero

Reported bugs

3 issues
  • Password reset problems
  • Inaccurate fasting time tracking
  • Inability to exit trial without subscribing

Requested features

6 requests
  • Custom fasting periods longer than 24 hours
  • Ability to edit fasting type and duration
  • Integration with more health/fitness apps
  • Water intake tracking
  • Personalized fasting recommendations
Show 1 more
  • Improved data visualization and analytics

Zero Fast

Not enough reviews yet to summarise bugs or requests.

In-app purchases

10 purchases

Zero

Subscriptions10
  • Zero Plus Subscription2 variants$9.991 Month
  • Zero Plus Subscription7 Days trial$9.991 Month
  • Zero Plus Subscription$39.991 Year
Show 7 more
  • Zero Plus Subscription7 Days trial$49.991 Year
  • Zero Plus Subscription7 Days trial3 variants$69.991 Year
  • Zero Plus Subscription$69.991 Year
  • Zero Plus Subscription1 Year trial3 variants$69.991 Year
  • Zero Plus Subscription1 Month trial$69.991 Year
  • Zero Plus Subscription1 Month trial$89.991 Year
  • Zero Plus Subscription7 Days trial$89.991 Year
2 purchases

Zero Fast

Subscriptions2
  • Zero Fast Monthly$3.991 Month
  • Zero Fast Annually$29.991 Year

Questions

Is Zero free?
Zero is free to download, with in-app purchases available.
Is Zero Fast free?
Zero Fast is free to download, with in-app purchases available.
Which has better reviews, Zero or Zero Fast?
Zero Fast is rated higher. Zero averages 4.8 out of 5 from 445K ratings, while Zero Fast averages 5.0 from 1 ratings.
Do Zero or Zero Fast have ads?
Neither Zero nor Zero Fast shows ads.
Which is updated more often, Zero or Zero Fast?
Zero ships an update every 2 weeks, and Zero Fast every 2 weeks. Most recently, Zero was updated on October 31, 2026 and Zero Fast on October 30, 2026.

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