Comparison

Sleepi.ai vs Cafactor

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

Head to head
About

Sleepi.ai

Features
Read full description

Why Sleepi is Special: - World's First AI Health Companion combining real-time health tracking with emotional intelligence - Seamless integration with Apple Watch for comprehensive health monitoring - Privacy-first approach - all your data stays in iCloud - Personalized health insights that evolve with you AI Companion Features: - Real-time health conversations - Emotional support when you need it - Proactive wellness suggestions - Natural, engaging interactions - Personalized motivation and encouragement Health Monitoring: - Comprehensive health data tracking - Beautiful, intuitive visualizations - Trend analysis and insights - Progress tracking - Customizable health goals Privacy & Security: - All data stored securely in iCloud - No server storage of personal data - Complete data control - GDPR compliant Perfect For: - Health enthusiasts seeking deeper insights - Busy professionals managing wellness - Anyone wanting a supportive health companion - Those looking for motivation and accountability - People seeking personalized health guidance Transform your health journey with Sleepi - where AI meets empathy, and technology serves wellness. Download now and experience the future of personal health companionship. Your wellness journey deserves more than just tracking - it deserves understanding, support, and guidance. Sleepi is here for you, 24/7. Requires iOS 15.0 or later and Apple Watch Series 4 or later Download Sleepi today and experience the world's first truly intelligent health companion.

About

Cafactor

This app models your body's real-time caffeine levels using a scientific pharmacokinetic approach. It helps you understand your caffeine absorption, decay, and personal sleep thresholds, adapting to your unique biology and activity. Connect with health data for an even smarter metabolic coaching experience.

Highlights
  • Real-time caffeine curve modeling
  • Personalized physiological parameters
  • HealthKit integration for adaptive coaching
  • Exercise and sleep-adaptive thresholds
  • HRV & Recovery integration
  • Progressive calibration of half-life
  • Offline, private tracking
Features
Read full description

Caffeine Hourglass is now Cafactor — rebuilt from the ground up. What began as a simple caffeine timer has evolved into a full physiological model that adapts to your biology in real time. Version 2.0 isn't an update. It's a new category of health tool. Know your caffeine. Protect your sleep. Log a drink in seconds. Cafactor computes your real-time caffeine curve using a peer-reviewed pharmacokinetic model — complete with a realistic absorption phase, first-order decay, and your personal biological parameters. See whether you can safely have one more coffee, and exactly when your levels will drop below your personal sleep threshold. Personalised to your body Set your sex, height, weight, and age. Cafactor applies the Boer (1984) lean-body-mass formula to calculate how caffeine distributes in your specific body. Add smoking status, hormonal medication, or pregnancy for a half-life that's truly yours. Your tolerance to caffeine — derived automatically from 7-day history — rounds out the picture. HealthKit: exponentially smarter Connect Apple Health and Cafactor transforms from a tracker into an adaptive metabolic coach: • Exercise modifier — Recent vigorous workouts temporarily speed up your metabolism. Cafactor detects this from HealthKit and adjusts your decay curve automatically. • Sleep-adaptive threshold — Last night's poor sleep tightens your safe window today. Great sleep? More room for your morning ritual. • HRV & Recovery (Apple Watch) — Daily heart-rate variability fuses with sleep quality to create a PhysiologicalState score, shifting your optimal intake windows and adjusting thresholds by up to 40%. • Progressive calibration — Recency-weighted regression over 30 days of sleep and HRV feedback automatically refines your personal half-life, growing from Preliminary to Reliable confidence as data accumulates. Pro features Unlimited history · Trend, sleep quality and scatter charts · Last safe caffeine time · Four smart notifications (morning window, safe window, withdrawal, recovery) · Shareable weekly report · Siri shortcuts · Unlimited custom drinks Free, forever, offline Core tracking is always free. No account. No internet. No data leaves your device — ever.

Screenshots

Sleepi.ai4 screens
Cafactor4 screens

Verdict

The call

The clearest difference is in-app purchases: Sleepi.ai at none against Cafactor's 1. Cafactor's advantage is device support (3 vs 1). On price, update cadence, ads 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. Cafactor sells 1 one-off in-app purchase. Sleepi.ai asks for nothing beyond the download.

UpkeepUpdate frequency

Sleepi.ai ships an update every 9 days, Cafactor weekly. The most recent releases landed on October 2, 2026 and September 25, 2026 respectively.

Scorecard2 real differences · 8 level
Sleepi.ai versus Cafactor: the parameters behind the verdict, then further details
ParameterSleepi.aiCafactor
PriceFreeFree
Rating—5.0 (1 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—1 — better
Update frequencyEvery 9 daysWeekly — better
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Freemium
DevicesiPhoneiPhone, iPad, Apple Watch — better
Requires iOS16.4 — better17.6
Further details — not scored
Size14 MB9 MB
Age rating12+4+
DeveloperShenzhen Infinite State Technology Co., LtdNan Yu

In-app purchases

None

Sleepi.ai

No in-app purchases

1 purchases

Cafactor

One-time1
  • Cafactor Pro$3.99

Questions

Is Sleepi.ai free?
Sleepi.ai is free to download, with no in-app purchases.
Is Cafactor free?
Cafactor is free to download, with in-app purchases available.
Do Sleepi.ai or Cafactor have ads?
Neither Sleepi.ai nor Cafactor shows ads.
Which is updated more often, Sleepi.ai or Cafactor?
Sleepi.ai ships an update every 9 days, and Cafactor weekly. Most recently, Sleepi.ai was updated on October 2, 2026 and Cafactor on September 25, 2026.

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