Affiliate Disclosure: By buying the products we recommend, you help keep the site alive. Read more.
I’ve always been a bit of a sleep experimenter, having for much of my life kept a meticulous dream diary and studied as much as I could about sleeping in the process. Nowadays, I don’t even need an alarm – my body wakes itself up exactly 8 hours after I close my eyes. If you’ve never given it a second thought, consider this: one third of your entire life is spent in bed (asleep, if you’re lucky), so you may as well make the best of it.
There are a number of apps now on both iOS and Android that claim to help you sleep better by waking you up at a good time. Let me explain how these apps can make such bold claims, and examine if they actually work. You might be surprised.
I’ll be looking at Sleep Cycle alarm clock on iOS ($1.99, iTunes link), and Sleep as Android (Google Play link: 2 week trial, $2.79 to unlock) – both offer essentially the same functionality and there are a number of clones knocking around the app stores. I’ve used the iOS app for a year or so, but have used the Android app only for a few days; however, it’s based on the same technology and as far as I can tell, it is an acceptable alternative for Android users.
We also covered a web app which does the reverse; it uses common sleep cycle data to tell you when to sleep given a desired wake up time, but don’t expect good results with that. No smart alarm or sleep app will help with your bad habits though, so be sure to read our general advice about improving sleep patterns as well before attempting to use these.
The Sleep Cycle
Sleeping is not as simple as just closing your eyes and shutting your consciousness off for a while. In fact, sleep occurs in roughly 4 stages, as follows:
- Stage N1: The lightest stage, a transition period between wakefulness and sleep, which lasts approximately 5-10 minutes. You can easily be awoken from this stage without any ill effects. Hypnagogic hallucinations and body twitches are common; sudden involuntary movements that can jerk you awake momentarily.
- Stage N2: Rapid, rhythmic brain activity. Your body temperature begins to decrease and heart rate slows. 40-55% of all sleep is spent in this stage.
- Stage N3: Deep sleep with strong delta waves. Still no dreaming.
- REM Sleep: a curious state in which the body is paralyzed, yet other brain and body functions are elevated. Dreaming occurs entirely during this state.
These stages don’t occur in sequence – N3 may be followed by more N2, for instance. However, most people will complete a full cycle 90 minutes after falling asleep; the first REM period is short, but as the cycle is repeated perhaps 4 or 5 times, the last REM period can last up to an hour and the full cycle may be 90-120 minutes long.
The reason why I’m telling you this is because the stage during which you wake up determines how you feel about the nights sleep; if your alarm rudely awakens you during REM or deep sleep, you feel groggy, with the desire to pull the covers over and hit snooze, but the damage is already done. This is technically termed sleep inertia. Awaken during one of the lighter periods of sleep though, and you’ll feel refreshed, as if you had a good night’s sleep. We can determine roughly what stage of sleep you’re in by the level of movement; more movement is a more wakeful stage, while sleep paralysis means less movement in the deeper stages. This what the apps we’ll be looking at today claim to do.
How Do These Apps Work Then?
Sleep as Android has more features, but assuming you only want to use it to wake up at a nice time, start by setting an alarm and the smart period, as well as your usual alarm sound etc. The rest of the options are pretty bewildering, but this is enough to get started. Your alarm should be the absolute latest you can wake up to without problems; but the app may wake you up anywhere in the smart period window before that time. Begin sleep tracking by tapping the very un-button-like Sleep tracking (with a half moon icon) in the bottom left of the app. That’s all that’s needed. Don’t hit the power button though – the app will automatically dim the screen after a while.
With Sleep Cycle, the interface is far simpler, and includes a placement test with a full walkthrough on usage, the first time you open the app. There are no multiple alarms; just choose the time and hit start.
Before going to sleep, open the app and place the device on the side of your bed, on your mattress – the placement is critical. You’ll also need it to be plugged in on charge, as it’ll be on all night and constantly recording your movements – a quick way to drain the battery.
For the first few nights, you’ll be woken up at your regular alarm time; the app is calibrating itself to your movements, so isn’t yet able to distinguish your wakeful and deep sleep phases. Persist though, and you’ll be rewarded with wonderful mornings where you can jump out of bed refreshed.
These apps work well, but only in specific circumstances.
If you sleep with a partner, their movements are also recorded by the accelerometer, which can give false readings of wakeful periods and therefore wake you at the wrong time. This depends on how vigorously your partner moves during sleep though, so it is best to have a go and try calibration anyway. You will get better results when you sleep alone, for certain.
Your bed also needs to be relatively bouncy in order to effectively pick up your movements; I found that it doesn’t work so well with foam type mattresses – the kind that is hard but mold to your body shape; nor with Japanese futons which just don’t have springs at all. Again, try it first though.
Lastly, these apps do require flexibility in your schedule – a 30 minute window is recommended – so if your morning is a mad dash to get the kids and breakfast ready, it probably won’t suit your lifestyle. If you are happy with the possibility of waking up 30 minutes before your usual time, but feeling much better for it, then you’ll do well. You can set a smaller window, but that reduces the chances of it being able to find an ideal wake up time.
In good conditions, I found that 9 times out of 10 SleepCycle would do as promised, waking me up feeling refreshed. It’s difficult to convey how incredible that feels, but your life will be better for it.
So there you have it; these things do work, and are actually based on real sleep science. They’re not perfect of course – but for the price of a coffee, I’d say it’s more than worth a try. I’ve also only begun to touch on the features here; the iOS Sleep Cycle is polished and reliable, but I have to say the sheer number of features of Sleep as Android is quite insane – check out the add-on apps too, like advanced sleep analysis.
Have you tried sleep tracking? Are you a passionate oneironaut? Tell us about your experience with these apps in the comments!