Comparison

Fastly vs Vow Fasting

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

Head to head
About

Fastly

This app provides a private and ad-free intermittent fasting timer with customizable schedules and progress tracking. It offers insights into fasting phases and integrates with Apple Health for goal monitoring.

Highlights
  • Real-time fasting timer
  • Customizable fasting plans
  • Estimated fasting phases
  • Fasting history and statistics
  • Weight and body fat goals
  • Apple Health integration
  • Smart reminders
Features
Read full description

Fastly is a clean, private fasting timer for 16:8, 18:6, OMAD, and custom schedules—without ads, accounts, or distractions. Start a fast with one tap, adjust your start or end time when needed, and see your elapsed time, remaining time, and planned finish at a glance. Fastly keeps the experience focused while giving you the tools you need to understand your routine and track your progress. FOLLOW YOUR FAST See estimated fasting phases based on your elapsed fasting time, including digestion, fat burning, ketosis, and autophagy. Upcoming phase markers make it easy to see what comes next during your fast. TRACK YOUR PROGRESS Review your complete fasting history through clear statistics, charts, and progress insights. Set weight and body fat goals, and optionally connect Apple Health to keep your measurements organized. STAY ON TRACK EVERYWHERE Follow your fasting status from your iPhone, Apple Watch, Home Screen widgets, and complications. Smart reminders help you stay aware of fasting goals and eating windows without unnecessary interruptions. KEY FEATURES • Real-time fasting timer with elapsed and remaining time • Planned fasting end time displayed at a glance • 14:10, 16:8, 18:6, 20:4, OMAD, and custom plans • Estimated fasting phases for digestion, fat burning, ketosis, and autophagy • Upcoming fasting phase markers • Complete fasting history with statistics and charts • Weight and body fat goals with progress benchmarks • Apple Health integration for weight and body fat • Apple Watch app and complications • Home Screen widgets for quick progress checks • Smart fasting and eating-window reminders • Optional private iCloud synchronization • Dark mode and a clean, focused interface PRIVATE BY DESIGN No ads. No third-party analytics. No developer data collection. Your fasting and health information stays on your devices and, when optional synchronization is enabled, in your private iCloud account. IMPORTANT NOTE Fasting phases are estimates based on elapsed time and can vary from person to person. Fastly is intended for general wellness and fasting tracking only. It does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before making medical or dietary decisions.

About

Vow Fasting

Read full description

Vow is a refined intermittent fasting tracker built for calm daily discipline. Start a fast, follow your progress, and understand each stage as your body moves through metabolic phases like digesting, fat burning, ketosis, and autophagy. Vow keeps fasting focused with a precise timer, clear progress, thoughtful reminders, and a minimal dark design made for daily practice. Whether you follow 16:8, 18:6, 20:4, 24-hour fasts, or custom fasting goals, Vow helps you track every session with clarity. FEATURES • Elegant fasting timer with real-time progress • Intermittent fasting plans including 16:8, 18:6, 20:4, and 24h • Metabolic phase tracking from digesting to fat burning, ketosis, and autophagy • Fasting history, streaks, and weekly insights • Custom and extended fasting durations • Goal reminders and phase update notifications • Minimal dark interface with premium themes • Home Screen widgets and Live Activity support Vow Pro Unlock extended fasting protocols, custom durations, premium themes, advanced insights, and premium widgets. Vow is not medical advice. If you have a medical condition, are pregnant, under 18, or have a history of eating disorders, consult a healthcare professional before fasting. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://vowfasting.com/privacy

Screenshots

Fastly4 screens
Vow Fasting4 screens

Verdict

The call

Fastly and Vow Fasting are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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. Fastly sells 4 one-off in-app purchases and Vow Fasting sells 2 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Fastly ships an update every 10 days, Vow Fasting fortnightly. The most recent releases landed on November 9, 2026 and November 5, 2026 respectively.

ScorecardNo meaningful differences
Fastly versus Vow Fasting: the parameters behind the verdict, then further details
ParameterFastlyVow Fasting
PriceFreeFree
Rating4.8 (96 ratings) — better—
Positive reviews94.1% of reviews—
Number of ratings96 — better—
Update frequencyEvery 10 days — betterFortnightly
AdsNoNo
In-app purchasesYesYes
MonetizationFree—
DevicesiPhone, Apple Watch — betteriPhone
Requires iOS17.617.6
Further details — not scored
Size9 MB13 MB
Age rating12+4+
DeveloperCollweb LLCFILIP LUCCA KEJSER DAMICI

In-app purchases

4 purchases

Fastly

One-time4
  • Coffee$1.99
  • Lunch$4.99
  • Become a Supporter$4.99
Show 1 more
  • Dinner$9.99
2 purchases

Vow Fasting

Subscriptions2
  • Vow Pro Monthly$4.991 Month
  • Vow Pro Annual$39.991 Year

Questions

Is Fastly free?
Fastly is free to download, with in-app purchases available.
Is Vow Fasting free?
Vow Fasting is free to download, with in-app purchases available.
Do Fastly or Vow Fasting have ads?
Neither Fastly nor Vow Fasting shows ads.
Which is updated more often, Fastly or Vow Fasting?
Fastly ships an update every 10 days, and Vow Fasting fortnightly. Most recently, Fastly was updated on November 9, 2026 and Vow Fasting on November 5, 2026.

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