Comparison

Optimal HRV vs sleep² sleeptracker & analysis

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

Head to head
About

Optimal HRV

Monitor, analyze, and improve your Heart Rate Variability (HRV) scores. This app offers personalized training, biofeedback, and stress-reducing activities to enhance health, reduce stress, and improve mental clarity.

Highlights
  • Real-time HRV monitoring
  • Personalized training plans
  • Guided meditation and breathing exercises
  • Comprehensive data analysis
  • Stress response insights
  • Biofeedback optimization
Features
Read full description

Are you feeling stressed, burned out, or just not yourself? Optimal HRV is the guided biofeedback app that teaches your body to calm down — for real. Backed by a Harvard Medical School mindfulness expert and trusted by athletes worldwide. Optimal HRV pairs real HRV data with live biofeedback, so every session trains your nervous system to handle stress better — not just tells you that you're stressed. Why HRV and Biofeedback Training Work Your Heart Rate Variability (HRV) is a window into how well your body handles stress, anxiety, and recovery — and biofeedback is how you train it to improve. Together, they show you what's happening inside your body, then guide you to change it in real time. With Optimal HRV, you can: • See how stressed — or relaxed — your body really is, using real HRV data. • Learn what actually helps you recover, from sleep to workouts to busy workdays. • Use live biofeedback to train your body to relax faster, right as it's happening. • Discover your own personal "perfect breathing rhythm" through guided sessions. Features You'll Actually Use • Daily Check-Ins — take a quick reading each morning, or anytime you want to see how you're doing. • Your Perfect Breathing Rhythm — a simple test finds the exact breathing pace that works best for you. • Live Feedback While You Train — a simple on-screen guide shows you when you're doing it just right. • Calming Mindfulness Sessions — guided practices created with a Harvard Medical School mindfulness expert, covering stress, anxiety, pain management, athletic performance, and more, with calming narrations in your choice of voice. • Easy-to-Read Progress — see your trends over days, weeks, and months, no data expertise needed. • Video Tutorials — learn HRV concepts and techniques at your own pace. • Make It Yours — adjust sounds, pacing, and reminders so training fits your life. • Available in 14 Languages — use Optimal HRV in your native language. • Device Testing — quickly verify if your heart rate monitor works with the app. • Great for Teams Too — employers and coaches can track group wellness together (Dashboard access needed). Why Optimal HRV Works with External Sensors (Not Apple Watch) We choose precision over convenience. Apple Watch is great for daily wellness, but Optimal HRV is built for serious HRV training. That's why we connect directly to an HRV monitor via Bluetooth — they deliver millisecond-accurate R‑R intervals that wrist sensors can't match. What that means for you: • More accurate data – better insights, better decisions. • Real-time streaming – no gaps, no guesswork. • Reliable results – trusted by athletes and coaches worldwide. Love Optimal HRV? Leave a review and help others find their calm. Your feedback helps us improve and reaches more people who need stress relief. Try it free for 30 days and feel the difference for yourself. Download now and start training your nervous system today. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

sleep² sleeptracker & analysis

This app acts as a personal guide to better sleep, combining innovative sleep training with precise sleep tracking and analysis. It offers an EU-approved medical device program for acute sleep disorders like insomnia, providing personalized recommendations and sleep training based on your data.

Highlights
  • Sleep tracking and analysis
  • Sleep training programs
  • Personalized recommendations
  • Interactive chatbot
  • Data import (Polar sensor, Apple Health)
  • Manual sleep diary entry
Read full description

Discover Sleep Anew: sleep² - Your Sleep Tracker sleep² is your personal guide to better sleep. It combines innovative sleep training with a precise sleep tracker. Sleep trackers provide valuable insights into your sleep. The sleep² Intensive Program is an EU-approved medical device, specifically designed for people with acute sleep disorders like insomnia. Our scientifically based method has already helped thousands improve their sleep quality through systematic and gradual sleep tracking and training. sleep² Pro: Based on sleep analysis, the program adapts to individual sleep data, delivering precise recommendations from your sleep tracker. Sleep Tracker: Analyze sleep using a Polar sensor or import data via Apple Health. Manually enter sleep data into the sleep diary if no tracker is used. Based on the sleep data, you get: Detailed recommendations based on sleep analysis Sleep training for better sleep An interactive chat-bot to help you sleep better Sleep analyses always available—no waiting like in sleep labs Precise sleep analysis through innovative algorithms for sleep improvement Free download & basic functions Full features of sleep² (precise sleep analysis, personalized programs) with subscription purchase Download sleep² - Our sleep tracker and precise sleep analysis help improve sleep! Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Optimal HRV4 screens
sleep² sleeptracker & analysis4 screens

Verdict

The call

The clearest difference is review sentiment: sleep² sleeptracker & analysis at 62% against Optimal HRV's 17%. sleep² sleeptracker & analysis also leads on rating (3.6 vs 3.0). Optimal HRV's advantage is iOS requirement (13.0 vs 15.0). On price, ratings volume, update cadence and ads 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. Optimal HRV sells 3 in-app purchases, starting at $9.99 per month and sleep² sleeptracker & analysis sells 4 in-app purchases, starting at $9.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

sleep² sleeptracker & analysis holds the better App Store score, 3.6 against 3.0. Both are backed by a comparable volume of ratings — 24 and 37 respectively. Written reviews point the same way: 17% of Optimal HRV's written reviews are positive against 62% of sleep² sleeptracker & analysis's.

UpkeepUpdate frequency

Optimal HRV ships an update fortnightly, sleep² sleeptracker & analysis every 2 weeks. The most recent releases landed on October 8, 2026 and October 22, 2026 respectively.

Scorecard3 real differences · 7 level
Optimal HRV versus sleep² sleeptracker & analysis: the parameters behind the verdict, then further details
ParameterOptimal HRVsleep² sleeptracker & analysis
PriceFreeFree
Rating3.0 (24 ratings)3.6 (37 ratings) — better
Positive reviews16.7% of reviews61.7% of reviews — better
Number of ratings2437 — better
Update frequencyFortnightly — betterEvery 2 weeks
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS13.0 — better15.0
Further details — not scored
Size52 MB110 MB
Age rating4+4+
DeveloperOptimal, LLCNukkuaa

Customer experience

Optimal HRV

All ratings24 ratings
Positive50.0%
Neutral0.0%
Negative50.0%
Written reviews12 reviews
Positive16.7%
Neutral0.0%
Negative83.3%

sleep² sleeptracker & analysis

All ratings37 ratings
Positive56.8%
Neutral8.1%
Negative35.1%
Written reviews60 reviews
Positive61.7%
Neutral6.7%
Negative31.7%

In-app purchases

3 purchases

Optimal HRV

Subscriptions3
  • 1 month1 Month trial$9.991 Month
  • 6 Month1 Month trial$47.996 Months
  • One Year1 Month trial$59.991 Year
4 purchases

sleep² sleeptracker & analysis

Subscriptions2
  • sleep² PRO$9.991 Month
  • sleep² PRO$79.991 Year
One-time2
  • sleep² intensive program$39.99
  • sleep² intensive program$99.99

Questions

Is Optimal HRV free?
Optimal HRV is free to download, with in-app purchases available.
Is sleep² sleeptracker & analysis free?
sleep² sleeptracker & analysis is free to download, with in-app purchases available.
Which has better reviews, Optimal HRV or sleep² sleeptracker & analysis?
sleep² sleeptracker & analysis is rated higher. Optimal HRV averages 3.0 out of 5 from 24 ratings, while sleep² sleeptracker & analysis averages 3.6 from 37 ratings.
Do Optimal HRV or sleep² sleeptracker & analysis have ads?
Neither Optimal HRV nor sleep² sleeptracker & analysis shows ads.
Which is updated more often, Optimal HRV or sleep² sleeptracker & analysis?
Optimal HRV ships an update fortnightly, and sleep² sleeptracker & analysis every 2 weeks. Most recently, Optimal HRV was updated on October 8, 2026 and sleep² sleeptracker & analysis on October 22, 2026.

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