Sleep and wake better with LARK, a revolutionary silent alarm clock and personal sleep coach. Developed with the world’s leading sleep experts, LARK works with its LARK Up app to evaluate your sleep data, empower you to improve, and wake you (and only you) silently with a vibrating alarm. Begin your sleep coaching experience with a 7-Day Sleep Assessment and within a week you're well on your way to a well-rested you.

Note: This app is intended to be used with a LARK wristband accessory.
To purchase one, please visit our website at

Silent Alarm Clock. Wake like never before – gently, and silently, without disturbing your sleeping partner.

• A silent and peaceful wakeup, designed with sleep experts to be highly effective

• No more disrupting your partner’s or roommate’s sleep with your noisy alarm clock

• Guaranteed alarm, even when phone battery dies

• Familiar alarm clock interface – large snooze button and numerical display

• Adjustable snooze time

• Peace of Mind feature: an adjustable backup audio alarm that plays composer-created audio
 if it does not receive a response from you within a few minutes after your alarm goes off.
• Automatically dimming clock interface.

Personal Sleep Coach. Helps you understand your sleep and guides you to improve it in the simplest and easiest ways.

• Micromovement wrist sleep pattern sensor picks up patterns while you sleep.

• 7-Day Sleep Assessment—a baseline assessment designed with sleep experts to uncover your Sleep Type.
• 7-Day Sleep Report-- a detailed report that gives you a personalized, actionable plan on how you can sleep better based on your sleep pattern data.
• Sleep Coach shows how you slept, how our sleep compares to both your average and healthy sleepers and monitors your sleep on a weekly, monthly and overall basis.
• Ability to tag factors and feelings to find out what is affecting your sleep and how your sleep affects your mood.
• Motivational coaching with messages as you improve and reach your sleep goal.

How does it work?

Use the LARK Up app to set your wake up time and alarm settings. Turn on the alarm and your iPhone will wirelessly transfer your alarm settings and sleep patterns to your LARK wristband. Strap on the lightweight, hassle-free wristband and go to sleep. The micromovement sensor will pick up your sleep patterns, and when it’s time to wake up, your LARK wristband will vibrate and nudge you awake. Press the big snooze button to snooze or slide the stop button across the screen to wake.

Your Personal Sleep Coach will then display your sleep quality and patterns immediately on your screen showing you how you slept during the night and how you fare in comparison to your average and healthy sleepers, all wirelessly. At the end of your 7th night of activating your 7-Day Sleep Assessment, your Personal Sleep Coach will unveil your Sleep Type and provide a personalized action plan and tailored sleep goals to help you improve your sleep.

Option: Use LARK Pro, a subscription upgrade, and your Personal Sleep Coach will be even richer with tools to help you sleep better.
Wake your potential. Not your partner.

What’s New

Version 1.2.11

+ Bug fixes

Ratings and Reviews

3.3 out of 5
249 Ratings

249 Ratings

bobwilliams ,

Great App, needs 1 feature to get a 5

If you are looking for a total solution to help you get more rest and plan for a more productive and fulfilling life, this is it. The App is perfect except it needs the ability to continue the tracking and alarm reset without starting a new session. I have a baby and a 2 year old that are often up at night, therefore I try to get a minimum of 6 hours sleep and after being interrupted sometimes for an hour I will extend my sleep by an hour. I tend to go to bed at 10 pm and get up around 4 am. Therefore I have the flexibility to add an hour if the kids keep me up in the middle of the night and not effect work. If the app would allow for the flexibility to do this I would give it a 5.

Regardless, thanks for this tool as its helped me get my erratic sleep habits under control and I'm less irritable and more energetic now throughout the day.

derekbaker ,

As an alarm clock, nearly perfect

I needed something that would wake me reliably but not disturb my husband. This -- the wristband plus the app -- is pretty much perfect for that. Any issues with Bluetooth pairing I've been able to resolve (they're infrequent, but annoying when they occur; fortunately, as the device is designed, they're discovered at bedtime and not after-the-fact). The one serious problem I had after an app update, customer service was able to help me fix via email. The wristband vibrates enough to wake me (I still set a soft back-up alarm gong across the room for 10 minutes later; I know me) without waking my husband. My one improvement to the app would be to allow me to estimate/add manually any additional sleep I get if I doze off on the couch, for a nap, etc. As it is, thi, "History" gives me a good, uh, wake-up call that I'm playing fast and loose with regular bedtimes and helps me keep a healthy night's sleep a priority ... or at least an (un)conscious goal.

SOCarro ,

Lark Up

The concept for this sleep tracker is not bad, but the execution is poor. To all appearances, the platform is not even being supported anymore. There have been no app updates since 2012; the developer website customer support also shows no interaction since 2012. The most useful function is the vibrating alarm, but it fails to work or fails to set because of pairing or other software issues far too often. It is very frustrating to have to spend 20 minutes, when you should be asleep, setting your alarm. I have submitted multiple service requests, none of which have received any reply. I rate this as high as one star only because I think that with decent tech support it could be a good device. I am hoping for a Vivosmart or Up3 for Christmas, after which I will be tossing the Lark. I have had it less than three months, but cannot put up with the poor reliability and poor interface any longer. If I had not received it as a gift, and had any idea where it was purchased, I would have returned it within the first month.


Lark Technologies, Inc
16.5 MB
Health & Fitness

Requires iOS 4.2.6 or later. Compatible with iPhone, iPad, and iPod touch.


English, French, German, Italian, Japanese, Simplified Chinese, Spanish, Traditional Chinese

Age Rating
Rated 4+
© 2015 LARK Technologies Inc.


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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