|November 29, 2023

We Tested Four Sleep Tracker Apps and Wearables: Here are the Best Ones

By Courtney Sperlazza, MPH
Reviewed for Scientific Accuracy

We Tested Four Sleep Tracker Apps and Wearables: Here are the Best Ones

  • Your sleep can make or break your day. That’s why sleep tracking apps have surged in popularity. Almost everyone could stand to improve sleep.
  • Epidemic proportions of people do not get enough sleep. Or they spend eight hours in bed, but have poor sleep quality. Poor sleep can lead to anything from feeling sluggish all day to chronic illnesses like depression and diabetes.
  • You can improve your sleep faster if you know what’s actually happening while you’re in bed.
  • There are so many sleep tracker apps available, from rings to watches and apps that use just your phone. Which sleep trackers work best?

Statistics show that a third of people reading this do not get enough sleep.[1] Not getting enough sleep makes you feel groggy and distracted, and it has long-term effects. Insufficient sleep increases your risk of conditions like:

  • Diabetes
  • Heart disease
  • Depression
  • Hormone imbalances
  • Cancer

There are hundreds of other conditions that can be traced back to poor sleep duration and quality. You could go to bed earlier, but is that the answer? Sleep isn’t just an on/off switch. As any insomniac knows, time in bed doesn’t necessarily translate to time asleep, recharging.

It’s easier to change something that you measure. Makes sense, because you can pinpoint opportunities for improvement when your current status is right in front of you in black and white.

Enter sleep tracker apps and wearables. The things you do during the day affect your sleep, and a lot happens behind the scenes when you’re sleeping. If you can see where your sleep stands today, you can zero in on small changes to improve your sleep and start feeling amazing.

Keep scrolling to see the best sleep trackers to improve your sleep and help you power up every single day.

Want to Sleep Better? Feel More Rested?

Bulletproof can help. Try our science-backed Sleep Guide for FREE.


If you’re interested in seeing how the things you do throughout your day affect your sleep and recovery, this is the wearable for you. With a full range of metrics and advanced analyses like the Readiness Score (more on that coming up), the OURA helps you see what’s happening under the hood while you’re sleeping. The more you can track, the easier it is to make small changes to see what helps you get the best possible night’s rest.

Compatibility: iOS, Android



  • Total sleep
  • Sleep efficiency
  • Tranquility
  • REM sleep
  • Deep sleep
  • Latency (time from pillow to falling asleep)
  • Timing
  • Body temperature
  • Heart rate variability
  • Respiratory rate
  • Calorie burn
  • Steps

Battery life: About a week


Readiness Score

The OURA takes a unique look at what makes a good night’s sleep. If you want to assess your sleep at a glance, you can pull up your Readiness Score in the OURA app. Your Readiness Score tells you if you’re ready for the day ahead, or if you should focus on rest and recovery. It uses information from your sleep the night before, your activity the day before and a handful of other measures to help you make decisions about the upcoming day.

Body temperature

The OURA tracks your average body temperature throughout the night, which can help you understand whether a difference in room temperature of a degree or two will make you feel your best the next day. Over the past month or so, I learned that choosing a light sheet over a thick blanket gives me about 17% more REM sleep, which is the restorative sleep phase. Sounds small, but how many more hours would I have to waste in bed to get that much more REM sleep?

Body temperature is also interesting if you’re tracking your menstrual cycle, though I wonder if it’s precise enough to use for fertility tracking. I’ve noticed a bump of about 0.3 degrees right around mid-month, which happens when your progesterone level elevates from ovulation. It drops back down around period time.

Heart Rate Variability

Heart rate variability (HRV) is a measure that is super sensitive to stress — not just emotional stress, but stress that you might not even know is happening.

On an episode of Bulletproof Radio (), co-founder and CEO of OURA Health, Harpreet Rai, explains how you can use the OURA ring’s HRV measure to inform the things you do during the day.

“People are starting to realize that if you eat a pint of ice cream before you go to bed, you end up having low heart rate variability and a high resting heart rate. Most people won’t get that great of deep sleep or REM sleep, and as a result, you sort of feel like crap the next day. So, I think you will start to realize that it’s actually your lifestyle actions that affect your sleep,” Rai explains.

Heart rate variability does not go into your readiness score, but it is a good indicator of how the things you do during the day affect your sleep at night. A higher nighttime HRV indicates that your body tolerates stress well, your stress management tactics are working or that you don’t deal with a lot of stress. Low HRV throughout the night tells you that you’re stressed, that your immune system is fighting something or that you’re reacting to a food or toxin that isn’t right for your biology. As you make changes to your diet and lifestyle, you can check in on your heart rate variability to see how it changes.

It’s worth a mention that the OURA is, in my opinion, the prettiest wearable tech you’ll find. I wore the Balance style in silver, which is smaller and more streamlined than the previous generation. I assumed any smart ring would look clunky on my small hands, but it looks great.

RELATED: Instantly download our 30-day Bulletproof Upgrade guide to take charge of your health and feel amazing every single day.

Motiv Ring

Since the Motiv excels at detecting restlessness, and my husband is the more restless sleeper of the two of us, I had him test the Motiv to see what it picks up.

Compatibility: iOS, Android



  • Active minutes
  • Resting heart rate
  • Activity types
  • Calories burned
  • Activity intensity
  • Steps
  • Sleep duration
  • Distance

Battery Life: 3 days


(As reported by the Mister … )

Sleep duration

The Sleep Length metric was amazingly accurate. I was having a lot of restless nights when I first started wearing it, waking up for five minutes to several hours. I can’t say with certainty how accurate it was down to the minute, but it seemed to catch every time I woke up with precision.

I did notice that a few nights when I had a few glasses of wine I actually seemed to have less restless sleep. We all know that alcohol negatively impacts the more restorative sleep phases, but the app told me I slept better. Was it just that I didn’t move as much, and my sleep quality did actually drop? Hard to say without a breakdown.

I would like to see more information on sleep phases. The app only tracked sleep length and restless sleep periods. My restless periods seemed consistent with what the app reported. For now, I am not really sure how to use the data. I could look for trends as far as restless times of night, and see what adjustments make a difference. Sleuthing out the problem would be easier if I knew where the interruptions fell along my sleep rhythms.

Activity tracking

Other measures like steps and heart rate all appeared accurate. As far as tracking time actively exercising, I ran into a snag: I lift heavy, so I wanted to remove the ring so I wouldn’t ruin it. That’s not unique to the Motiv — it’s a downside of all rings.

It’s a beautiful ring – I started wearing it in place of my wedding band. It’s easy to charge, and the app has a simple and intuitive interface. A few times, I had a difficult time picking up the signal to sync it with the app, but overall it worked well. So far, it seems to be pretty scratch-resistant too. I only scratched it once noticeably when I was sitting on a rock and scraped it. How it would hold up in the long run, though, is anyone’s guess.

Fitbit Charge 3

Fitbit Charge 3Among the most well-known wearables, the Fitbit Charge 3 offers solid sleep tracking and activity tracking, and it integrates with your phone to alert you of incoming calls, texts and appointments. The Fitbit best suits people who want to optimize their exercise, with sleep as part of that goal.

Compatibility: iOS, Android

Cost: Starts at $149


  • Steps
  • Miles
  • Calories burned
  • Active minues
  • Heart rate
  • Run/bike mapping
  • Time in heart rate zones
  • Sleep duration
  • Sleep phases
  • Self-logged measures like weight and hydration


The following review was written for the Fitbit Charge 2.

Challenges and social elements for motivation

If it’s motivation you’re after, the Fitbit keeps you going. You can get any level of motivation that works for you, from buzzes throughout the day that remind you to get up and move, to completing challenges with friends who are also using the app. If you’re more likely to stick with a program if you have someone keeping you accountable, the Fitbit has your back.


If you’re distractible, you’ll want to rein in your notifications when you start. Text messages, movement reminders, appointment in your calendars, challenge alerts, social notifications … they all add up. Spend some time in the beginning setting up which notifications serve you and your goals, and silence the ones that don’t.

That said, I found the Fitbit to be less distracting than my phone. I could have it on my wrist and quickly decide whether to respond to a text, rather than sifting through every notification that I had on my phone every time a text came through.

Sleep tracking

The Fitbit logged my sleep cycles as much more erratic than the other trackers did. It said I woke 3-4 times each night, but I don’t recall waking at all. I sleep continuously throughout the night and I wake up feeling refreshed, so I’m inclined to believe that the other trackers hit the mark a little better. Since I’m unconscious, it’s hard to say which of them is the most accurate, though.

This is personal preference, but I’m not a fan of having something on my wrist while I sleep. Perhaps I could get used to it, but three nights in, I still took it off halfway through the night. Compared to the rings, which I forgot about soon after putting them on, I noticed the watch at night.

Sleep Cycle app

The Sleep Cycle app senses your sleep cycles using your phone’s microphone and accelerometer (movement sensor). It analyzes breathing and movements to determine when you’re awake, in deep sleep or in REM sleep.

You tell the app when you need to wake, then you place your phone next to your pillow or on your nightstand when you hit the sack. The app will decide when you’re in your lightest sleep phase around your programmed wake-up time, so you’re not trying to fight against deeper sleep phases.

Cost: Free, or $29.99 per year for Premium

Platforms: iOS, Android


Free version:

  • Intelligent wake-up
  • Sleep analysis
  • Nightly sleep graph
  • Alarm melodies
  • Snooze
  • Apple Health integration (iPhone only)
  • Database export (iPhone only)

Premium offers several additional features like online back-up, a wake-up mood tracker and integration with your smart light bulbs and running tracker.


Wake up gently

Generally, I wake on my own without an alarm. When I have to use an alarm, I’m not exactly the spring-out-of-bed type. I call it waking up gently. My husband calls it quit hitting the $%&! snooze button. The app promises to wake you during light sleep, making it easier to rouse when it’s time. I tested the alarm function to see if waking up felt like a gentle nudge, or if I would be tempted to hit snooze eleventy thousand times.

I set the alarm to wake me around 6:00 a.m., even though I naturally wake up between 6:30-7:00 a.m. The app takes that to mean that any time I caught a light sleep phase between 5:30-6:00 a.m. is fair game.

I found that it was surprisingly easy to wake up at the alarm time every day I used the alarm function, which led me to believe the app accurately detected my light sleep phase. If I wanted to snooze, I had the option to use an “intelligent snooze” function, and the alarm lapse would shorten each time I hit it. I didn’t need to use it, though. Quite a departure from my normal alarm wake-ups with multiple snoozes.


I had no idea an iPhone mic was so sensitive. I downloaded the app in the afternoon, when I was nowhere near ready to go to sleep. Before I closed it, I noticed the sound detection line flexing as I breathed normally, my face about a foot away from my phone. It picked up every little sound, even down to my own relaxed breaths that I couldn’t hear myself.

I wondered whether it would pick up my husband’s breathing and motion if he was sleeping next to me. We go to bed at different times and his night sleep is fairly erratic, whereas I sleep hard. The app undoubtedly logged my bedtime and sleep pattern, not his. He came to bed late and was up and moving several times one night, while I stayed asleep in bed, so I was sure it didn’t make a mistake.

Doesn’t a phone next to your head expose you to harmful EMFs (electromagnetic fields) all night? Technically yes, and that will mess with your circadian rhythm and has some long-term effects. Luckily, there’s an easy fix: switch to Airplane Mode and you’re good to go.

You’ll see benefits no matter which sleep tracker you choose. The important thing is that you have a general sense of what’s happening while you sleep, and you’re taking steps to improve it. Being Bulletproof is all about paying close attention to how changes make you feel and spotting trends so that you can do more of what works and feel amazing every day of your life.

Want to Sleep Better? Feel More Rested?

Bulletproof can help. Try our science-backed Sleep Guide for FREE.