Sleep Monitor FAQ


1.What does Sleep Monitor do?

Sleep Monitor is a health & fit app focusing on tracking sleep phases.
Sleep Monitor provides deep insights into quality of your sleep by the following metrics:
    -Sleep Score
    -Sleep Cycle Graphic
    -Sleep Statistics
    -Sleep Noise

Besides, Sleep Monitor helps you mark different sleep behaviors. Still, it provides various relaxing music to help you fall asleep faster and also provides a smart alarm to help you wake up on time.

2.How does sleep tracking work in Sleep Monitor?

Sleep Monitor uses both microphone and accelerator sensor on your phone to measure your body movements and your environmental noise changes and then recognize your sleep phases. Your body movements are directly related to your sleep phase. In general, the more movements or the more sleep noises, the lighter sleep will be.

According to the reports of sleep specialists, during the night, your body follows certain sleep cycles. It goes from light sleep to deep sleep and occasionally goes into the REM-sleep, where dreaming occurs. During light sleep phase, you tend to toss and turn, making environmental noises. In deep sleep phase, your muscle movements are suppressed with less noise made. REM phases are not directly detected from your body movements. Rather, the estimation is based on statistical analysis.

Sleep Monitor computes sleep score and creates a sleep graph for your sleep according to the measurement results. Those statistic insights help you indicate whether your sleep is healthy or not.

3.What is Sleep Monitor’s scoring matrix? How does Sleep Monitor rate a good sleep?

Sleep Monitor has its own scoring algorithms with taking many factors into account, such as the whole sleep length, deep sleep ratio, personal feeling in the morning, and the physical conditions. Referring to specialists' advice, we adjust the weights of each factor to make the score more accurate and more consistent with that from professional equipment monitoring like PSG (Polysomnography). A high score reflects you get a good sleep with long time sleep duration and more deep sleep, vice versa.

4.How does REM measured in Sleep Monitor?

REM is the acronym of Rapid Eye Movement, which, according to sleep researchers, is a sign of dreaming. There is no way to tell if there actually was REM at any particular moment, based solely on aggregate activity data.

IAs REM phases are not directly detected from your body movements, REM in Sleep Monitor is just an estimation based on statistical analysis. When there is a long enough deep sleep period followed by a long enough light sleep period, we mark the first half of the light sleep as REM. People usually dreams about three to five times every night, with 5-15mins duration each time. But this varies upon physical condition, mental condition etc. We are adjusting our algorithms to make the REM more accurate.

5.How does Sleep Monitor know I am in deep sleep?

Mobile phone has an accelerometer sensor which is very sensitive and if placed by your bed, phone can make a record of your movement over the night. Body movements are directly related to your sleep phase.

In light sleep phase, you tend to toss and turn, to make movements and environmental noises. In deep sleep phase, your muscular movements are suppressed (otherwise you would be running or jumping around according to your dreams. Thus, in this phase you will be quiet with almost no movements. Sleep Monitor uses both microphone and accelerator sensor in your phone to measure your body movements. This is in short how Sleep Monitor measures your sleep phases.

6.No Sleep record found when wake up.

This issue may occur in below situations:
1).This issue happens when Android system randomly kills apps running in background to save battery. When Sleep Monitor was killed, sleep tracking will be interrupted so there will be no sleep report generated. To prevent this issue from occurring again, please follow this guide to keep Sleep Monitor always running based on your device type: dontkillmyapp

2). This issue may happen when phone RAM is not enough. There will be no storage for our app to keep running or save your report. Please make sure there is enough space to save sleep records.

7.Will sleep tracking be accurate when I have a dog / cat sleeping with me in bed?

It depends on several factors. The general rule is to not allow the pet to move your phone, ideally only your movements should move the device. So in this case it’s best to place your device either under the pillow. If your pet is a quiet one, it may just work. However, if your pet is used to jump in and out of bed several times during the night, the sleep tracking will most probably register these events as light sleep occurrences.

8.Why sleep graph seems to be fake? Will Sleep Monitor generate random data?

Sleep Monitor will not generate random data as it has own algorithm to draw sleep graph. As you may know, Sleep Monitor measures your body movements and draws sleep graph according to both microphone and accelerator sensor on your phone. Because each accelerometer (in different cell phones) measures movements differently, we couldn’t assume any standard conversion formula would respond to absolute values. We are working on to adjusting algorithm to draw graph from time to time to make sure sleep tracking is accurate.

9.Can I export sleep records?

Your sleep records (score, graph, statistic, noise recording) will be saved in Sleep Monitor app side but cannot be exported currently. And there are limits for data saving:
    - 1. Sleep Monitor free version users can save 7 sleep records
    - 2. Sleep Monitor pro version users can save up to 30 sleep records
In app side, only latest new records will be saved, old records will be deleted automatically when reach limits.
If you want to clear all sleep records, try this way: phone settings/apps/Sleep Monitor/Clear data.
Please note you can share all sleep noises recordings with friends. Sleep Monitor pro users can even download sleep noises recordings.

10.How to restore my sleeping records after I reinstall the app or clear app data?

Sleep Monitor free version: Free version user can save up to 7 sleep records on phone local storage, not on cloud. If you uninstall app and re install, or clear app data then back to app again, the old records will be gone.

Sleep Monitor Pro version: Pro version users can save up to 30 sleep records on phone and backup all sleep records on cloud storage. Please always remember to backup sleep records. If you uninstall app and re install, or clear app data then back to app again on the same device, the previous sleep records will be restored automatically on your phone. Due to network connect issue, if the records are not synchronized in time please just click the Restore button manually to get old records.

Please note that if you delete any sleep record on local storage, it will never come back again.

11.Does Sleep Monitor function in background mode?

Yes. Background mode is fully supported. After you open Sleep Monitor and click the “Start to Sleep” button you can allow it to run on background to track sleep. As long as you don’t quit app, it works. But we do recommend you keep app running in the foreground as Android system will kill background process randomly.

12.What noise does Sleep Monitor record? Sleep talk or just snore?

Sleep Monitor records all kinds of noises that sound different from ambient noises and saves 12 obviously sleep noises, with each noise lasting maximally 1 minute. Both sleep talk and snore will be recorded. At this moment, Sleep Monitor could not tell whether the noise is dream talk or snore. But we are working on distinguishing it.

13.Where are sleep noises recordings saved?

The default path to save sleep noises recordings is: phone storage/sleepmonitor/sleepnoise. We suggest you go to File Manager on your phone to find recordings: tap “search” - enter “sleep monitor”, it can locate the path successfully.

14.Do you store any sound?

All audio recordings are stored on your phone but they can be shared(a link of your local storage) with others. Pro user can backup recordings on Cloud manually for latter checking. The truth is that if you don’t share recordings with anyone they will remain private on your phone. You can decide if you want to share it with us when you have concerns about a specific sound recording, which will help us to locate issue.

15.Will the shared sleep noise recordings be expired?

Both free and pro users can share your sleep noise recording with others. The shared link is valid within 7 days. You need to re-click the “Share” button to generate a new link when old link expires.

16.Sleep Monitor Free vs. Premium Features

Sleep Monitor is a free-to-use app with advanced subscription and in-app ads.Sleep Monitor free version users can enjoy all basic features like sleep tracking, listen to and share all audio files, free sleep music,alarm clock, sleep graph analysis, etc.
When upgrade to Pro, you can unlock more advanced features:
    - Save more sleep records on phone
    - Download sleep audio recordings
    - Unlock sleep trends(weekly/monthly/yearly statistics)
    - Add customized sleep factors
    - Backup all sleep reports on Cloud
    - Unlock all sleep music
    - No ads
    - More coming features

17.How to get a refund?

It’s less than 48 hours since you bought an app or made an in-app purchase, you can request a refund through Google Play by yourself. For more details about refund please visit:

18.How do I cancel my Premium subscription?

We are sorry we cannot deal with it for you directly. Your subscription is tied to your ID with Google Account, only you can cancel your subscription. We can guide you, please follow the below steps:
    - 1. Open and log in to your Google Play account
    - 2. Tap the main menu. It’s located at the left top
    - 3. Tap Subscriptions
    - 4. Tap Sleep Monitor
    - 5. Tap Cancel Subscription
For more details, please check the following link:

19.I’ve subscribed the Premium/Pro, why the App is still not unlocked?

In this situation your subscription may not be synchronized due to some reasons. Please try to restore your purchase first as follow: Open app →click Crown icon on right top→Restore

Your purchase info will be restored on your phone. If this won't help,you can either contact, or use the More → Feedback, directly from the app. Our support team will help to restore your Premium.

20.I bought a Premium/Pro on Android device, can I use it on my iOS device?

We are really sorry that we are unable to transfer your subscription from Android devices to iOS devices since they are running on different platforms. There is no user system in Sleep Monitor right now. All subscriptions are device based.
Anyway we can take this as a suggestion and try to improve it in future updates.

21.Can I use my own music as a wake up/sleeping melody?

Currently, Sleep Monitor doesn't support loading local music into the app for the sleeping music/alarm ringtone. We will try to implement this feature in later updates. We will appreciate it a lot if you can contact us at to tell us what kind of music you like so we can try to add it into our app.

22.How to set the music playing duration when sleep?

Sleep Monitor supports to set the following music playing duration:
    - 10 minutes
    - 20 minute
    - 30 minute
    - 45 minute
    - 1 hour
    - Auto (The default duration of the music itself)
Please do it as procedures below: Click on the playing music name → then you will be led to Lullabies → find the clock icon on the bottom and click it → select duration

23.Alarm clock is not working in the morning.

This issue happens when Android system randomly kills Sleep Monitor running in background to save battery. When Sleep Monitor is killed, alarm clock fails to work. To prevent this issue from occurring again, please follow this guide to keep Sleep Monitor always running to work normally based on your device type: dontkillmyapp. We are now working on fixing this issue in following updates.

24.What should I do if I have troubles with Sleep Monitor?

If you find any error or unexpected incorrect behavior please send us feedback via this way: Sleep Monitor - More –Feedback. Describe your troubles with key words and brief steps to reproduce troubles, and then send it to us via email, we will look into it ASAP. Please feel free to contact us if you have any questions or suggestions.

25.How to change language?

Sleep Monitor supports more than 20 languages, such as English, German, French, Japanese, Chinese, Italian, Korean, Hungarian, Portuguese, Spanish, Dutch, Polish, Turkish, Finnish, Vietnamese, Arabic, Indonesian, Persian, Bulgarian, Czech, Catalan, Ukrainian, Breton…
When first installed, Sleep Monitor shows the same language as your system. If you would like to change language, please uninstall it to change phone default language in system settings, and then re-install it. We will add the function of switching languages in app in later updates. To be a volunteer for translation, please contact us via this way: Sleep Monitor - More - Help us Translate

26.Is there any way to connect my data with Google fit app?

Currently Sleep Monitor does not support this feature. We will add Google fit support in later updates.

27.Does Sleep Monitor supports smart wearable device?

Sorry that at present Sleep Monitor doesn't support smart wearable device. Nevertheless, we are working on it. Please stay tuned.

28.Does Sleep Monitor drain a lot of battery?

Generally, Sleep Monitor will use an average of 20% battery per night (7 to 8 hours) for sleep tracking. When noise recording is turned on, it might jump up to 30%. To prevent high battery usage, we suggest you kill any unnecessary services before starting sleep tracking.

29.Why App says “Sleep tracking is intermittent and part of the data was lost. Still, show sleep report?”?

This issue may occur in several situations:
1).This issue usually happens when the Android system randomly kills apps running in the background to save battery. When Sleep Monitor is killed, sleep tracking will be interrupted so there will be no sleep report generated. To prevent this issue from occurring again, please follow this guide to keep Sleep Monitor always running according to your device type: dontkillmyapp

2)This issue may happen when phone RAM is not enough. There will be no space for our app to keep running or save your report. Please make sure there is enough space to save sleep records.

30.Why App says “Sleep Monitor detected unusual sleeping behavior, no record has been generated.”?

Users will receive this message when the tracking time is over 24 hours. App will judge this long time sleeping as abnormal behavior so no records will be generated. So, please try tracking within 24 hours.

31.Do you have a Privacy policy?

Yes. All your data is perfectly safe with us, and we never share personal data with any third parties.
More about our Privacy Policy can be found through:

32.I have found an error in translation of the app

This is great! Please drop us a line on or contact us through More/Feedback from the app.

33.I have a good idea/suggestion for your app.

Your valuable suggestion/feedback are well welcomed. Please don't hesitate to contact us at or chat with us through More/Feedback from the app.

34.Why is it asking me for permission to use the microphone?

Sleep Monitor and other sleep apps use phone’ s microphone for sleep movements tracking and sleep sound recording then measure sleep phases. If microphone permission is denied you can still use the app by using phone accelerometer to measure sleep phases.

But we strongly suggest you allow microphone permission if you really want to track sleep to get sleep insights as microphone tracking will be more sensitive than accelerometer.