Comparison

Zero vs Fastime

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

Fastime

Features
Read full description

Fastime is a simple, private intermittent fasting tracker that helps you start a fast, stay consistent and actually see your progress. Pick a plan, start the timer, and follow your body through each fasting stage. Fastime handles the rest. FASTING TIMER & PLANS • Seven plans: 12:12, 14:10, 16:8, 18:6, 20:4, 24:0 and fully custom • Live countdown with a progress ring, and the exact time your fast ends • Eating-window timer so you know when to eat • Not sure where to start? Answer 5 quick questions and get a plan made for you • A summary when every fast ends: how long, the stage you reached, and how it felt FASTING STAGES Follow your body in real time through Fed → Fat Burning → Ketosis → Autophagy → Deep Fast, with a short note on what each stage means. HOME SCREEN WIDGET See your current fast and your streak without opening the app. PROGRESS & INSIGHTS • Day streaks and a weekly report: total fasting time, average, longest fast and consistency • Month calendar with every completed fast and weight entry • Weight log with a goal weight, and body metrics including BMI • See how your fasts felt over time • Full fasting history AI FASTING COACH Personal weekly insights built from your own fasting pattern, generated entirely on your device. WATER & STEPS • Daily water tracking with your own cup size and reminders • Step counting with a daily goal STREAKS, ACHIEVEMENTS & CHALLENGES • Streak Protection keeps your streak alive on near-miss fasts • Unlock achievements as you go • Challenges from a 3-day starter all the way to 100 fasts SMART REMINDERS Notifications when your fast starts, at halfway, at key stages, when it's complete, and before your eating window ends, plus an optional daily reminder to start fasting. APPLE HEALTH Optionally sync your completed fasts and weight with Apple Health. YOUR DATA, ON YOUR DEVICE Your fasting history, weight and logs are stored on your device. Export a backup or a CSV any time, and if you reinstall, restore your fasts and weights from Apple Health. 10 LANGUAGES English, Arabic, Swedish, French, Spanish, German, Portuguese, Russian, Chinese and Japanese, with full right-to-left support for Arabic. Start your first fast today.

Screenshots

Zero4 screens
Fastime4 screens

Verdict

The call

The clearest difference is in-app purchases: Fastime at none against Zero's 10. Fastime also leads on update cadence (every 2 days vs every 2 weeks) and iOS requirement (15.1 vs 17.0). Zero's advantage is chart position (#109 vs unranked). On price, ads and device support 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 7 in-app purchases, starting at $9.99 per month. Fastime asks for nothing beyond the download.

UpkeepUpdate frequency

Zero ships an update every 2 weeks, Fastime every 2 days. The most recent releases landed on November 3, 2026 and October 24, 2026 respectively.

Scorecard4 real differences · 7 level
Zero versus Fastime: the parameters behind the verdict, then further details
ParameterZeroFastime
PriceFreeFree
Rating4.8 (445K ratings) — better—
Positive reviews32.0% of reviews—
Number of ratings445K — better—
Update frequencyEvery 2 weeksEvery 2 days — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreemium—
Best chart rank#109 — better—
DevicesiPhone, Apple WatchiPhone, iPad, iPod — better
Requires iOS17.015.1 — better
Further details — not scored
Size195 MB59 MB
Age rating17+4+
DeveloperZero Longevity Science, Inc.Khaled Almelhem

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

Fastime

Not enough reviews yet to summarise bugs or requests.

In-app purchases

7 purchases

Zero

Subscriptions7
  • Zero Plus Subscription2 variants$9.991 Month
  • Zero Plus Subscription7 Days trial$9.991 Month
  • Zero Plus Subscription7 Days trial2 variants$69.991 Year
Show 4 more
  • Zero Plus Subscription$69.991 Year
  • Zero Plus Subscription1 Year trial2 variants$69.991 Year
  • Zero Plus Subscription1 Month trial$69.991 Year
  • Zero Plus Subscription7 Days trial$89.991 Year
None

Fastime

No in-app purchases

Questions

Is Zero free?
Zero is free to download, with in-app purchases available.
Is Fastime free?
Fastime is free to download, with no in-app purchases.
Do Zero or Fastime have ads?
Neither Zero nor Fastime shows ads.
Which is updated more often, Zero or Fastime?
Zero ships an update every 2 weeks, and Fastime every 2 days. Most recently, Zero was updated on November 3, 2026 and Fastime on October 24, 2026.

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