Comparison

JustFast vs Keepfasting

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

Head to head
About

JustFast

This app offers a straightforward intermittent fasting timer. It focuses on tracking your fast with a clear, calm interface, providing insights into metabolic stages without gamification or pressure. It prioritizes privacy with on-device data storage and no accounts.

Highlights
  • One-tap start and stop
  • Live timer with accurate timekeeping
  • Metabolic milestone tracking
  • Plain-language explanations of milestones
  • Adjustable start/stop times
  • Ongoing notification for duration
  • Simple history of past fasts
  • 18 languages and dark design
Features
Read full description

Fasting is a beautifully simple intermittent-fasting timer that does one thing well: it tracks your fast. No goals to hit. No streaks to protect. No accounts, no ads, no clutter. Just tap once to begin, and a calm live timer counts your fast while a glowing ring fills toward the next stage your body moves through. WHY IT'S DIFFERENT Most fasting apps pile on dashboards, reminders, and pressure. This one strips fasting back to its essence — a clear timer you can glance at and put away. It's designed to feel quiet and focused, not gamified. WHAT YOU GET • One-tap start and stop, with a big, satisfying button • A live timer that keeps perfect time across restarts, time-zone changes, and daylight saving • Metabolic milestones — the ring fills toward the next stage (blood sugar settling, glycogen burning, fat burning, ketosis, autophagy, and more) • Tap any milestone for an honest, plain-language explanation of what's happening in your body • Forgot to start the timer? Just tap the ring to fix your start time. Forgot to stop? End your fast at the right time after the fact. • An ongoing notification shows your current duration at a glance • A simple history of past fasts — swipe to delete • 18 languages and a clean dark design HONEST BY DESIGN The milestone descriptions are written plainly and honestly. Where the science is still early or based mostly on animal research, we say so. This app is a timer and an educational companion — not medical advice. PRIVATE BY DEFAULT Your data stays on your device. There are no accounts, no sign-ups, no tracking, and nothing is uploaded. Fasting works for 16:8, OMAD, alternate-day, extended fasts, or any schedule you like — because it never forces a schedule on you. Note: Fasting is not a medical device and does not provide medical advice. Talk to a healthcare professional before starting any fasting regimen, especially if you are pregnant, nursing, taking medication, or have a medical condition.

About

Keepfasting

Features
Read full description

Keepfasting is a simple, intermittent fasting timer built around one idea: you should be able to glance at your Home Screen and instantly know whether you can eat. No accounts to create and no calorie counting. Just a clear countdown and a widget that tells you what you need to know at a glance. TWO WAYS TO TRACK Fixed Schedule Set the time your eating window opens once, and it repeats automatically every day. No daily interaction required. Log My Meals Tap "I Just Ate" or "Start Fasting" whenever it happens, and the app times your cycle from there. A WIDGET THAT'S ACTUALLY USEFUL Add Keepfasting to your Home Screen or Lock Screen and see your current phase in red for fasting or green for eating, with a live countdown that updates in real time. In Dynamic mode, a quick-log button on the widget lets you log a meal without even opening the app. A PROGRESS RING WORTH LOOKING AT Choose whether the ring fills up as your phase progresses or counts down as your deadline approaches, whichever mental model works best for you. A custom slider lets you fine-tune your plan with the red and green split as the control itself. REMINDERS, IF YOU WANT THEM Turn on optional local notifications for when your eating window opens and when it closes. They're off by default, so the app stays out of your way until you ask for it. ANY PLAN YOU LIKE Choose from quick presets like 16:8, 18:6, and 20:4, or fine-tune any custom schedule from 12:12 to 23:1 to match your routine. Your data stays on your device. There is no account, no login, and nothing to sync to a server. Download Keepfasting and start your next fast with a clear view of where you stand.

Screenshots

JustFast4 screens
Keepfasting4 screens

Verdict

The call

JustFast and Keepfasting are too close to call on the numbers: across 5 compared parameters — price, ads, in-app purchases and device support 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. Neither carries in-app purchases, so what you see is what you pay.

ScorecardNo meaningful differences
JustFast versus Keepfasting: the parameters behind the verdict, then further details
ParameterJustFastKeepfasting
PriceFreeFree
Rating4.5 (2 ratings) — better—
Number of ratings2 — better—
Update frequencyFortnightly—
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad — betteriPhone
Requires iOS18.017.0 — better
Further details — not scored
Size20 MB5 MB
Age rating4+4+
DeveloperVitalii VyrodovLars Ursprung

In-app purchases

None

JustFast

No in-app purchases

None

Keepfasting

No in-app purchases

Questions

Is JustFast free?
JustFast is free to download, with no in-app purchases.
Is Keepfasting free?
Keepfasting is free to download, with no in-app purchases.
Do JustFast or Keepfasting have ads?
Neither JustFast nor Keepfasting shows ads.

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