Comparison

WaterFast vs The Fast

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

Head to head
About

WaterFast

This app provides a synchronized intermittent fasting timer designed for seamless use across your iPhone and Apple Watch. It offers detailed insights into fasting zones and hydration tracking, with a focus on privacy and a user-friendly experience.

Highlights
  • Synchronized iPhone and Apple Watch timer
  • Fasting zone insights
  • Hydration tracking
  • Multiple fasting plans
  • Streak calendar
  • Data export
Features
Read full description

Some fasting apps charge many times more. WaterFast is a fraction of that — with a 3-day free trial on every plan. You decide. FASTING APPS HAVE A PROBLEM They're either overpriced, bloated with social feeds and AI coaching you never asked for — or they're simple but their Apple Watch app runs a separate countdown that drifts out of sync with your iPhone. Two timers for the same fast. Not optimal. WATERFAST IS DIFFERENT One timer. One source of truth. Your Watch doesn't follow your iPhone — it leads. Start, monitor and end your fast right from your wrist, even with your iPhone in your pocket. When you pick it up, everything matches. Always. To the second. TRY IT ALL FREE FOR 3 DAYS Start a 3-day free trial and unlock everything — no strings attached. Then keep it monthly, yearly, or one-time lifetime. Cancel anytime. EVERYTHING INCLUDED • Every plan: 16:8, 18:6, 20:4, OMAD, 5:2 and fully custom • Start & stop fasts from Apple Watch — it leads, iPhone follows • Live timer with progress ring and fasting zones • Streak calendar — don't break the chain, unlimited history • All Apple Watch complications (circular, corner, inline, rectangular) • Hydration tracking with one-tap logging and daily goal • Full stats: current streak, longest fast, total hours, success rate • Export your data as CSV • No account required BUILT FOR APPLE WATCH — REALLY Most fasting apps treat the Watch as an afterthought. WaterFast was designed wrist-first. The timer state lives in one shared place: start a fast on your Watch during dinner, check the zone on your iPhone the next morning — same fast, same seconds, zero drift. KNOW YOUR FASTING ZONES Track exactly what's happening in your body — from digestion through fat burning and ketosis to autophagy. Each zone explained in plain language, with science-based hour ranges. Educational reference only — not medical advice. HYDRATION, ON YOUR WRIST Log a glass of water with one tap on your Watch, with haptic confirmation, synced instantly to your iPhone and Apple Health. A PRICE THAT RESPECTS YOU WaterFast PRO: monthly, yearly, or one-time lifetime. Every plan starts with a 3-day free trial. We think a fasting timer shouldn't cost more than your streaming service. PRIVATE BY DESIGN No account. No ads. No tracking. Your fasting and hydration data never leaves your device (except to your own Apple Health, if you choose). Start your 3-day free trial and run your first fast in under a minute. --- Medical disclaimer: WaterFast provides educational information about fasting. It is not medical advice. Consult your healthcare provider before starting any fasting protocol, especially if you have a medical condition, are pregnant, or take medication. --- Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

The Fast

Features
Read full description

Fasting, at your pace. Choose a duration and start. A slowly moving record marks the time, with elapsed time and time remaining always within reach. ON YOUR HOME SCREEN Small and medium widgets keep your fast in view. See elapsed time at a glance, or use the larger widget for the full record, progress and time remaining. A MONTH, ON RECORD Browse your fasting history in a simple calendar. Finished goals retain their record color. Early endings appear in gray. Open any day to see each fast. YOURS TO SHARE Share one fast or your whole month as a single image. Include record details and exact times when you want to. LIGHT BY DESIGN Use the timer, history and widgets without an account. Your records stay on your device unless you choose to sync them. Optional Apple, Google or email sign-in lets you keep records across devices. Free to use. No ads. The Fast records time. It does not provide medical or dietary advice.

Screenshots

WaterFast4 screens
The Fast4 screens

Verdict

The call

The clearest difference is in-app purchases: The Fast at none against WaterFast's 2. The Fast also leads on update cadence (daily vs weekly). On price, ads, device support and iOS requirement 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. WaterFast sells 2 in-app purchases, starting at $9.99 per year. The Fast asks for nothing beyond the download.

UpkeepUpdate frequency

WaterFast ships an update weekly, The Fast daily. The most recent releases landed on October 6, 2026 and October 11, 2026 respectively.

Scorecard2 real differences · 8 level
WaterFast versus The Fast: the parameters behind the verdict, then further details
ParameterWaterFastThe Fast
PriceFreeFree
Rating5.0 (2 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings2 — better—
Update frequencyWeeklyDaily — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreemium—
DevicesiPhone, Apple Watch — betteriPhone
Requires iOS17.016.4 — better
Further details — not scored
Size3 MB31 MB
Age rating4+4+
DeveloperLUIS ORLANDO LAZO GONZALEZPrime Adventure LLC

In-app purchases

2 purchases

WaterFast

Subscriptions1
  • WaterFast PRO Yearly$9.991 Year
One-time1
  • WaterFast PRO Lifetime$24.99
None

The Fast

No in-app purchases

Questions

Is WaterFast free?
WaterFast is free to download, with in-app purchases available.
Is The Fast free?
The Fast is free to download, with no in-app purchases.
Do WaterFast or The Fast have ads?
Neither WaterFast nor The Fast shows ads.
Which is updated more often, WaterFast or The Fast?
WaterFast ships an update weekly, and The Fast daily. Most recently, WaterFast was updated on October 6, 2026 and The Fast on October 11, 2026.

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