Comparison

Sleep Time+ Cycle Alarm Clock vs REM Sleep Tracker

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

Head to head
About

Sleep Time+ Cycle Alarm Clock

Understand your sleep patterns and wake up feeling refreshed. This app tracks sleep cycles, offers soothing soundscapes for falling asleep, and measures resting heart rate without wearables. It provides detailed analysis and customizable alarms to optimize your sleep and wake-up experience.

Highlights
  • Sleep cycle analysis
  • Soothing soundscapes
  • Resting heart rate measurement
  • Smart alarm clock
  • Detailed sleep graphs
  • Apple Health integration
Features
Read full description

Fall asleep, stay asleep, and wake up refreshed! Sleep Time is a complete sleep tracker and smart alarm clock. Place your phone on the bed and Sleep Time analyzes your sleep cycles through the night, then wakes you during your lightest sleep within your chosen window — so you start the day rested instead of groggy. Trusted by over 35 million users, Sleep Time is an award-winning sleep app. ------------------ 5/5 “I finally understand why I wake up tired some mornings. Sleep Time showed me my sleep cycles, and the smart alarm has made my mornings so much easier — I haven’t hit snooze in weeks.” 5/5 “I’ve tried several apps that log sleep duration and stages, and the interface of Sleep Time is the best by far. It’s easy to understand and simple to use.” 5/5 “Fascinating results. It works remarkably well providing helpful information.” Featured on: TechCrunch, Mashable, Lifehacker, 148apps, eHealth, and many others. ----------------- MAIN FEATURES √ Set the alarm clock with a single gesture √ Fall asleep to soothing soundscapes and white noise √ Alarm rings even in silent mode √ Choose from 20 built-in alarm sounds √ Wake up to your favorite song from your music library √ Sleep Lab™ with light, deep, and REM sleep analysis √ Detailed daily, weekly, and monthly graphs √ Smart wake-up window for a gentler start to the day √ Full history makes night-to-night comparison easy √ Cloud backup and restore for your sleep data √ Clear, easy-to-read interface √ Apple Health integration We build Sleep Time for our users and would love your feedback. Tell us what you think so we can keep improving the app. Upgrade to Premium for unlimited soundscapes, advanced sleep insights, priority support, and an ad-free experience with an auto-renewable subscription. We offer auto-renewable subscriptions with the following terms: - Payment will be charged to your iTunes account at confirmation of purchase - Subscription automatically renews unless auto-renew is turned off at least 24 hours before the end of the current period - Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user's Account Settings after purchase - No cancellation of the current subscription is allowed during active subscription period - Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication - Our privacy policy and terms of use: https://www.azumio.com/page/privacypolicy Sweet Dreams, Azumio Team

About

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.

Highlights
  • 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
Features
Read full description

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

Screenshots

Sleep Time+ Cycle Alarm Clock4 screens
REM Sleep Tracker4 screens

Verdict

The call

The clearest difference is review sentiment: Sleep Time+ Cycle Alarm Clock at 69% against REM Sleep Tracker's 0%. Sleep Time+ Cycle Alarm Clock also leads on rating (4.8 vs 4.2) and ratings volume (2.5K vs 49). REM Sleep Tracker's advantage is monetization model (freemium vs subscription) and ads (none vs shown). 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Sleep Time+ Cycle Alarm Clock sells 8 in-app purchases, starting at $4.99 per month and REM Sleep Tracker sells 2 in-app purchases, starting at $9.99 per year. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Sleep Time+ Cycle Alarm Clock holds the better App Store score, 4.8 against 4.2. That said, the two scores are not equally well evidenced: Sleep Time+ Cycle Alarm Clock has 2.5K ratings behind it against 49, so its average is the more settled of the two. Written reviews point the same way: 69% of Sleep Time+ Cycle Alarm Clock's written reviews are positive against 0% of REM Sleep Tracker's.

UpkeepUpdate frequency

Sleep Time+ Cycle Alarm Clock ships an update monthly, REM Sleep Tracker every 2 weeks. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

Scorecard6 real differences · 4 level
Sleep Time+ Cycle Alarm Clock versus REM Sleep Tracker: the parameters behind the verdict, then further details
ParameterSleep Time+ Cycle Alarm ClockREM Sleep Tracker
PriceFreeFree
Rating4.8 (2.5K ratings) — better4.2 (49 ratings)
Positive reviews68.8% of reviews — better0.0% of reviews
Number of ratings2.5K — better49
Update frequencyMonthlyEvery 2 weeks — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationSubscriptionFreemium — better
DevicesiPhoneiPhone
Requires iOS16.016.0
Further details — not scored
Size185 MB25 MB
Age rating4+4+
DeveloperAzumio Inc.Nicola Eusebi

Customer experience

Sleep Time+ Cycle Alarm Clock

All ratings2,482 ratings
Positive95.3%
Neutral1.0%
Negative3.7%
Written reviews459 reviews
Positive68.8%
Neutral7.0%
Negative24.2%

REM Sleep Tracker

All ratings49 ratings
Positive79.6%
Neutral6.1%
Negative14.3%
Written reviews1 reviews
Positive0.0%
Neutral100.0%
Negative0.0%

Bugs and requests

Sleep Time+ Cycle Alarm Clock

Reported bugs

4 issues
  • Crashes on startup
  • Freezing issues
  • Inconsistent alarm behavior
  • Lost sleep data after updates

Requested features

4 requests
  • Heart rate monitoring integration
  • Sleep data export and analysis
  • Apple Watch companion app
  • More customization options

REM Sleep Tracker

Not enough reviews yet to summarise bugs or requests.

In-app purchases

8 purchases

Sleep Time+ Cycle Alarm Clock

Subscriptions8
  • Premium$4.991 Month
  • Premium$8.991 Month
  • Premium$9.991 Month
Show 5 more
  • Premium7 Days trial2 variants$9.991 Month
  • Premium$19.993 Months
  • Premium$29.991 Year
  • Premium1 Month trial2 variants$29.991 Year
  • Premium$46.991 Year
2 purchases

REM Sleep Tracker

Subscriptions2
  • Sleep Score Premium Yearly$9.991 Year
  • Sleep Score Premium Yearly7 Days trial$29.991 Year

Questions

Is Sleep Time+ Cycle Alarm Clock free?
Sleep Time+ Cycle Alarm Clock is free to download, with in-app purchases available.
Is REM Sleep Tracker free?
REM Sleep Tracker is free to download, with in-app purchases available.
Which has better reviews, Sleep Time+ Cycle Alarm Clock or REM Sleep Tracker?
Sleep Time+ Cycle Alarm Clock is rated higher. Sleep Time+ Cycle Alarm Clock averages 4.8 out of 5 from 2.5K ratings, while REM Sleep Tracker averages 4.2 from 49 ratings.
Do Sleep Time+ Cycle Alarm Clock or REM Sleep Tracker have ads?
Sleep Time+ Cycle Alarm Clock shows ads; REM Sleep Tracker does not.
Which is updated more often, Sleep Time+ Cycle Alarm Clock or REM Sleep Tracker?
Sleep Time+ Cycle Alarm Clock ships an update monthly, and REM Sleep Tracker every 2 weeks. Most recently, Sleep Time+ Cycle Alarm Clock was updated on November 1, 2026 and REM Sleep Tracker on November 3, 2026.

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