Comparison

Caffeine Tracker vs Whistle

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

Head to head
About

Caffeine Tracker

Log your caffeine intake from various beverages and understand its impact on your sleep and health. Get personalized 'Last Call' times and track trends with detailed charts and AI-powered custom drink analysis.

Highlights
  • Log various caffeine sources
  • Predict caffeine-free times
  • Calculate bedtime caffeine levels
  • Personalized 'Last Call' alarms
  • Analyze caffeine's impact on sleep
  • Custom drink creation with AI
  • Detailed charts and graphs
Features
Read full description

Alyx is a silly way to track caffeine. Quickly log espresso, lattes or anything else and see how it affects your health, sleep or view other interesting stuff! It uses Apple Health to store your data privately, which means it also syncs with iCloud. Of course, you can log caffeine here. Aside from being a coffee, espresso, energy drink, or general caffeine tracker and journal, there are some interesting things it can do: - Figure out when your body will be caffeine free. - Discover how much caffeine will be in your body at bedtime. - Get your customized "Last Call" for caffeine every day, and set an alarm for it! - See how caffeine consumption impacts the amount of sleep you get. - View how caffeine will decline in your body over the next 12 hours. - See if your caffeine consumption has been trending up or down lately. - Tons of Siri Shortcuts. - Tons of widgets! - Create your own custom drinks, and have AI figure out the caffeine contents! - A Hall of Fame for...caffeine consumption? - Um, what else? Oh, tons of charts! So yeah, you can see how caffeine affects your sleep, overall health, see how much sleep you'll lose, and more. I don't know, it's just a fun app. Download it or don't. Love, Alyx -- SUBSCRIPTION & PREMIUM FEATURES -- Most of Alyx is completely free to use. There are premium features if you upgrade to The Caffeine Club, which includes every widget, adding your own custom drinks, several charts, and sleep forecast features. -- LEGAL -- · View our terms of service here: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ · View our privacy policy here: https://alyxcaffeinetracker.com/privacy/ Subscriptions will be charged to your credit card through your iTunes account. Your subscription will automatically renew unless canceled at least 24 hours before the end of the current period. You will not be able to cancel the subscription once activated. Manage your subscriptions in Account Settings after purchase.

About

Whistle

This AI-powered app creates personalized training plans for running, cycling, swimming, and strength exercises. It adapts to your schedule and goals, providing insights into your training load, recovery, and progress. Seamlessly integrates with Apple Watch and HealthKit for comprehensive data analysis.

Highlights
  • AI-driven personalized training plans
  • Adaptive workout adjustments
  • Progress tracking and insights
  • Integration with Apple Watch and HealthKit
  • Weather-aware planning
  • Privacy-first data handling
Features
Read full description

Whistle is an AI training planner for running, cycling, swimming, strength work, and everything in between. Build a plan around your goals, adapt it when life changes, and understand what your training is doing over time. Plan with a coach that understands your week Ask Whistle to build a training week, create a longer program, adjust a workout, review your progress, or explain what your body is telling you. Your coach can use your goals, schedule, recent workouts, recovery, sleep, vitals, and local weather to help you make better training decisions. Training programs, not just single workouts Start a guided setup, tell Whistle what you are training for, and get a structured program you can follow week by week. Already following a plan? Bring that structure into Whistle and let your coach help you keep it organized. Workout planning that stays flexible Plan workouts for today, the week ahead, or a longer training block. Create structured sessions with warmups, intervals, targets, cooldowns, and activity-specific goals. Save workouts as templates so repeated sessions are ready when you need them. Train with better context Whistle turns workout and health data into practical planning support: - Training load to understand how much work you are absorbing - Projected load to see how planned workouts may shape your week - Recovery, sleep, and vital trends for daily context - Workout predictions for distance, duration, calories, and load - Training insights, heatmaps, and streaks to review consistency over time - Weather-aware planning with multi-day forecasts for outdoor sessions Apple Watch ready Send planned workouts to Apple Watch and start them from your wrist. Whistle also works with Apple’s Workout app experience, so your sessions fit into the tools you already use. Works with Apple Health (HealthKit) When you choose to share Apple Health data, Whistle can use workouts, activity, heart rate, recovery, sleep, and vitals to make planning and coaching more personal. The goal is useful training insight, not medical advice. Built privacy-first No account is required. Your workout and health data are handled with care, stored locally and in your personal iCloud where possible, and used only to power the features you choose. When AI processing is needed, Whistle uses the data required for the task instead of building a long-term personal profile on our servers. Some features require Pro or Ultra. Health, weather, watch, and AI features depend on device capabilities, permissions, region, and data availability.

Screenshots

Caffeine Tracker4 screens
Whistle4 screens

Verdict

The call

The clearest difference is rating: Caffeine Tracker at 4.9 against Whistle's 4.3. Caffeine Tracker also leads on review sentiment (79% vs 50%) and update cadence (every 5 days vs monthly). Whistle's advantage is device support (3 vs 1) and iOS requirement (18 vs 26.0). On price, ads, in-app purchases and monetization model 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 Tracker sells 4 in-app purchases, starting at $1.99 per month and Whistle sells 5 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Caffeine Tracker holds the better App Store score, 4.9 against 4.3. Both are backed by a comparable volume of ratings — 41 and 11 respectively. Written reviews point the same way: 79% of Caffeine Tracker's written reviews are positive against 50% of Whistle's.

UpkeepUpdate frequency

Caffeine Tracker ships an update every 5 days, Whistle monthly. Both last shipped on November 8, 2026.

Scorecard6 real differences · 4 level
Caffeine Tracker versus Whistle: the parameters behind the verdict, then further details
ParameterCaffeine TrackerWhistle
PriceFreeFree
Rating4.9 (41 ratings) — better4.3 (11 ratings)
Positive reviews78.9% of reviews — better50.0% of reviews
Number of ratings41 — better11
Update frequencyEvery 5 days — betterMonthly
AdsNoNo
In-app purchasesYesYes
MonetizationFreemiumFree with in-app purchases
DevicesiPhoneiPhone, iPad, Apple Watch — better
Requires iOS26.018 — better
Further details — not scored
Size45 MB100 MB
Age rating4+17+
DeveloperDay Well Spent LLCVogelhaus Apps GmbH

Customer experience

Caffeine Tracker

All ratings41 ratings
Positive97.6%
Neutral0.0%
Negative2.4%
Written reviews19 reviews
Positive78.9%
Neutral5.3%
Negative15.8%

Whistle

All ratings11 ratings
Positive81.8%
Neutral0.0%
Negative18.2%
Written reviews2 reviews
Positive50.0%
Neutral0.0%
Negative50.0%

In-app purchases

4 purchases

Caffeine Tracker

Subscriptions3
  • Caffeine Club$1.991 Month
  • Caffeine Club Annual$9.991 Year
  • Caffeine Club Annual7 Days trial$9.991 Year
One-time1
  • Caffeine Club: Lifetime$24.99
5 purchases

Whistle

Subscriptions5
  • Pro 1 Month$4.991 Month
  • 1 Ultra Month$9.991 Month
  • Ultra 3 Months3 Days trial$24.993 Months
Show 2 more
  • Pro 1 Year7 Days trial$39.991 Year
  • Ultra 1 Year$99.991 Year

Questions

Is Caffeine Tracker free?
Caffeine Tracker is free to download, with in-app purchases available.
Is Whistle free?
Whistle is free to download, with in-app purchases available.
Which has better reviews, Caffeine Tracker or Whistle?
Caffeine Tracker is rated higher. Caffeine Tracker averages 4.9 out of 5 from 41 ratings, while Whistle averages 4.3 from 11 ratings.
Do Caffeine Tracker or Whistle have ads?
Neither Caffeine Tracker nor Whistle shows ads.
Which is updated more often, Caffeine Tracker or Whistle?
Caffeine Tracker ships an update every 5 days, and Whistle monthly. Most recently, Caffeine Tracker was updated on November 8, 2026 and Whistle on November 8, 2026.

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