Comparison

Caffeine Clock vs Clarity

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

Head to head
About

Caffeine Clock

This app helps you track your caffeine intake and understand its impact on your sleep. It models caffeine absorption and half-life to provide a clear view of your current and projected levels, allowing you to plan your consumption for better rest.

Highlights
  • Caffeine absorption and half-life modeling
  • Real-time caffeine level tracking
  • Interactive home screen widgets
  • Sleep-aware insights and bedtime planning
  • Extensive drink database with custom options
  • Daily caffeine threshold alerts
Features
Read full description

Track your caffeine and sleep better. See exactly when today's coffee wears off. Caffeine Clock is a caffeine tracker that models absorption and half-life to estimate how much caffeine is in your system throughout the day. Log what you drink or eat, see how levels rise and fall, and plan your last cup so you can sleep with confidence. Accurate tracking with absorption rate Not just totals. Caffeine Clock models how quickly you absorb caffeine and how it declines (half-life), then estimates your level now and later. If you note how long you sipped that cappuccino, the curve updates accordingly. A clear, actionable dashboard An attractive graph shows your current level, projected decline, and how much caffeine you'll have at any time. Long-press to scrub the timeline and reveal exact values. At a glance, know whether you're in the clear - or whether another cup will push you past your comfort zone. Interactive Home Screen Widgets Monitor your stats without even opening the app. View your live caffeine curve and current mg count directly on your Home Screen. Need to log a refill? Use the quick-add widget to track your favorites with a single tap - keeping your data accurate with zero friction. Sleep-aware insights Set a target bedtime. If your projected level looks high by then, Caffeine Clock lets you know early, often before you even add a drink, so you can adjust your cut-off and protect tonight's sleep. Tuned to you A quick setup captures your habits and sensitivity, and you can adjust your personal caffeine half-life at any time in Settings, so the curve matches how your body actually clears caffeine. 200+ drinks, plus your own Choose from a built-in database of coffees, teas, and energy drinks, or create custom drinks with your own sizes and mg. Fast logging means better tracking. Thresholds and gentle alerts Pick a daily caffeine limit that fits your routine, whether that is the commonly cited 400 mg for adults or the 200 mg guideline many people follow during pregnancy. Get timely reminders before you overdo it. Apple Health Send every logged drink to Apple Health so your caffeine sits next to your sleep and the rest of your health data. Private and fully offline No account, no signup. Your data stays on your device, with an option to transfer locally. Caffeine Clock works fully offline. Anytime, anywhere. Made for everyday routines Whether it's espresso at 8, tea at 2, or an energy drink before a workout, Caffeine Clock shows how today's choices affect tonight's sleep, so you can enjoy what you love without second-guessing it. How it works - Log a drink from the 200+ library or use the quick-add widget. - The app models absorption and half-life to estimate your level over time. - Watch the live caffeine curve and countdown on the dashboard or Home Screen. - Set a bedtime and get informed if you may still be "too caffeinated" by then. Why a dedicated caffeine tracker? Caffeine affects everyone differently. A general health app won't tell you when a 3 PM latte will still be in your system at 10 PM. Caffeine Clock focuses on one job: timing your intake for better days and better nights. Get started in minutes Install, finish the onboarding, log your first drink, and watch your caffeine curve come to life. Disclaimer Caffeine Clock provides estimates based on published half-life ranges and your inputs. It's for informational purposes only and is not a medical device or a substitute for professional advice.

About

Clarity

This app helps you understand the impact of caffeine on your sleep, energy, and focus. Log your intake quickly and visualize how caffeine's half-life affects your daily cycles and nighttime rest.

Highlights
  • Fast caffeine logging
  • Caffeine half-life tracking
  • Sleep and recovery insights
  • Focus and energy analysis
  • Daily and weekly insights
Read full description

Clarity is the simplest way to understand caffeine's real impact on your sleep, energy, and focus. Log your intake fast and see how caffeine's half-life affects your entire day — from your 2PM coffee to your nighttime sleep cycles. • Fast caffeine logging and visualization • Caffeine half-life tracking and prediction • Athletes: see how caffeine affects your sleep and recovery • Focus and energy insights, daily and week-by-week Understand your 3PM crash. Improve your sleep by seeing your caffeine carry-over. Use caffeine deliberately, not accidentally. By using this app, you agree to Apple's Terms of Use (https://www.apple.com/legal/internet-services/itunes/dev/stdeula/) and our Privacy Policy.

Screenshots

Caffeine Clock4 screens
Clarity4 screens

Verdict

The call

The clearest difference is monetization model: Caffeine Clock at free against Clarity's freemium. Caffeine Clock also leads on ratings volume (27 vs 2) and iOS requirement (16.4 vs 18.0). Clarity's advantage is rating (5.0 vs 4.7) and review sentiment (100% vs 80%). On price, update cadence, ads and in-app purchases 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. Caffeine Clock sells 2 one-off in-app purchases and Clarity sells 2 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Clarity holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Caffeine Clock has 27 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 80% of Caffeine Clock's written reviews are positive against 100% of Clarity's.

UpkeepUpdate frequency

Caffeine Clock ships an update weekly, Clarity every 2 weeks. The most recent releases landed on October 20, 2026 and October 16, 2026 respectively.

Scorecard5 real differences · 5 level
Caffeine Clock versus Clarity: the parameters behind the verdict, then further details
ParameterCaffeine ClockClarity
PriceFreeFree
Rating4.7 (27 ratings)5.0 (2 ratings) — better
Positive reviews80.0% of reviews100.0% of reviews — better
Number of ratings27 — better2
Update frequencyWeekly — betterEvery 2 weeks
AdsNoNo
In-app purchasesYesYes
MonetizationFree — betterFreemium
DevicesiPhoneiPhone
Requires iOS16.4 — better18.0
Further details — not scored
Size121 MB25 MB
Age rating4+17+
DeveloperANTONIN WINGENDERNexus Nexus

Customer experience

Caffeine Clock

All ratings27 ratings
Positive92.6%
Neutral3.7%
Negative3.7%
Written reviews5 reviews
Positive80.0%
Neutral20.0%
Negative0.0%

Clarity

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

2 purchases

Caffeine Clock

One-time2
  • Remove ads$4.99
  • Remove Ads$9.99
2 purchases

Clarity

Subscriptions2
  • Clarity Plus - Monthly3 Days trial$2.991 Month
  • Clarity Plus - Yearly$19.991 Year

Questions

Is Caffeine Clock free?
Caffeine Clock is free to download, with in-app purchases available.
Is Clarity free?
Clarity is free to download, with in-app purchases available.
Which has better reviews, Caffeine Clock or Clarity?
Clarity is rated higher. Caffeine Clock averages 4.7 out of 5 from 27 ratings, while Clarity averages 5.0 from 2 ratings.
Do Caffeine Clock or Clarity have ads?
Neither Caffeine Clock nor Clarity shows ads.
Which is updated more often, Caffeine Clock or Clarity?
Caffeine Clock ships an update weekly, and Clarity every 2 weeks. Most recently, Caffeine Clock was updated on October 20, 2026 and Clarity on October 16, 2026.

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