REM Sleep Tracker vs HydraIQ
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
REM Sleep Tracker
This app analyzes Apple Watch sensor data to provide a sleep quality score. It offers detailed insights into sleep stages, heart rate, and weekly trends, helping users understand and improve their rest habits.
- Sleep quality scoring
- Detailed sleep stage analysis (light, deep, REM)
- Heart rate monitoring
- Weekly trend tracking
- Sleep bank concept for habit analysis
- Apple Health integration
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Sleep Monitor is the perfect app for people eager to enhance the quality of their nighttime rest. Thanks to an advanced algorithm, Sleep Monitor processes the data gathered by your Apple Watch sensors to provide you with an overall score representing the quality of your sleep. This innovative app offers a detailed analysis of the different sleep stages, monitoring light, deep, and REM sleep cycles, and providing information about your heart rate throughout the night. Additionally, Sleep Monitor allows you to track your progress with the "sleep bank" concept, a repository of your rest data that helps you better understand your habits and identify any issues. With Sleep Monitor, you can also monitor the weekly trends of various parameters, such as sleep duration, rest quality, and time spent in each sleep stage. This valuable information will enable you to make targeted lifestyle changes to improve your nighttime rest. Don't miss the opportunity to transform your Apple Watch into a powerful tool for better sleep and waking up more rejuvenated each day. Sleep Monitor is the ideal app for those seeking an ally in sleep management, with an intuitive design and a rich array of features. Download Sleep Monitor today and begin your journey towards more restful and regenerative sleep. Maximize the potential of your Apple Watch and discover how quality rest can improve your daily life! HealthKit Integrated with Apple Health for sleep stages, heart rate, respiratory frequency, age and gender data to calculate sleep quality. Sleep Monitor Premium Sleep Monitor offers a Premium version available as an auto-renewable subscription. Payment will be charged to iTunes Account at confirmation of purchase. Subscriptions automatically renew unless auto-renew is turned off at least 24-hours before the end of the current period. Account will be charged for renewal within 24-hours prior to the end of the current period at the rate of your selected plan above. Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user's Account Settings on the device. Once purchased, refunds will not be provided for any unused portion of the term. Privacy policy: http://app.sleepscoreapp.com/Home/Privacy Terms of use: http://app.sleepscoreapp.com/Home/Terms
HydraIQ
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Track every glass and build a daily hydration habit. HydraIQ adapts your daily goal to your weight and activity, sends gentle reminders, and visualises your streak. Most hydration apps just tally glasses. HydraIQ predicts when your body is heading toward dehydration and nudges you before thirst kicks in. Powered by live weather, your Apple Watch heart-rate signals, and your daily patterns. • SMART DAILY TARGET — Recalculated live from your weight, temperature, humidity and activity. No static 2-litre rule. • PREDICTIVE ALERTS — HydraIQ spots the gap between when you drank last and what your body needs, and nudges you with a friendly notification a few minutes BEFORE you'd feel thirsty. • APPLE WATCH COMPLICATION — Watch face complication with your live hydration state (Well Hydrated / Drink Soon / Hydrate Now) and percent of daily target. Log a drink straight from your wrist. • CLEAN DAILY DASHBOARD — At a glance: your target, what's been logged, and how you're trending through the day. • WEATHER-AWARE GOALS — Hot day? Humid? HydraIQ raises your target automatically so you don't fall behind. • DRINK TYPES THAT MATTER — Water, sports drinks, and coffee are tracked separately. Coffee counts at 70% hydration because caffeine is mildly diuretic. • FULL HISTORY — See your hydration trend over days, weeks and months. HYDRAIQ PRO HydraIQ Pro unlocks the predictive brain: • Predictive hydration alerts that learn your habits • Apple Watch complication on all watch faces • Weather-aware dynamic goals • Unlimited history and trends • Skin-type aware recommendations Subscribe: Monthly £1.99 or Annual £14.99 (best value — saves over 37%). Payment is charged to your Apple ID on confirmation of purchase. Subscription auto-renews unless cancelled at least 24 hours before the end of the current period. Manage or cancel in Settings > Apple ID > Subscriptions. Terms of Use: https://maddisys.co.uk/terms Privacy Policy: https://maddisys.co.uk/privacy HydraIQ does not sell your data. Health data is stored on your device.
Screenshots
Verdict
The clearest difference is ads: REM Sleep Tracker at none against HydraIQ's shown. HydraIQ's advantage is update cadence (every 6 days vs every 2 weeks). On price, in-app purchases, device support 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
Both are free to download. REM Sleep Tracker sells 2 in-app purchases, starting at $9.99 per year and HydraIQ sells 2 in-app purchases, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.
REM Sleep Tracker ships an update every 2 weeks, HydraIQ every 6 days. Both last shipped on October 24, 2026.
| Parameter | REM Sleep Tracker | HydraIQ |
|---|---|---|
| Price | Free | Free |
| Rating | 4.2 (49 ratings) — better | — |
| Positive reviews | 0.0% of reviews | — |
| Number of ratings | 49 — better | — |
| Update frequency | Every 2 weeks | Every 6 days — better |
| Ads | No — better | Yes |
| In-app purchases | Yes | Yes |
| Monetization | Freemium | — |
| Devices | iPhone | iPhone, Apple Watch — better |
| Requires iOS | 16.0 — better | 17.0 |
| Further details — not scored | ||
| Size | 25 MB | 10 MB |
| Age rating | 4+ | 12+ |
| Developer | Nicola Eusebi | Maddisys Limited |
In-app purchases
REM Sleep Tracker
- Sleep Score Premium Yearly$9.991 Year
- Sleep Score Premium Yearly7 Days trial$29.991 Year
HydraIQ
- HydraIQ Pro Monthly$1.991 Month
- HydraIQ Pro Annual7 Days trial$14.991 Year
Questions
Is REM Sleep Tracker free?
Is HydraIQ free?
Do REM Sleep Tracker or HydraIQ have ads?
Which is updated more often, REM Sleep Tracker or HydraIQ?
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