Lots of people buy fitness trackers for their sleep tracking capabilities. Pick up any of Fitbit’s more expensive devices, for example, and it’ll not only give you a summary of how long you spend asleep every night but also a detailed breakdown of how much time you spend in light, deep and REM sleep phases.

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This might sound useful but there are two problems with using a fitness tracker in this way. First, wearing a device on your wrist at night is not for everyone. Even the most slimline and discreet of wearables can feel uncomfortable in bed and end up hampering your ability to get a good 40 winks. The other problem is that, should you ever forget to wear your watch or need to remove it charge it, you’ll end up left with glaring gaps in your sleep log.

What’s the solution? Say hello to Nokia’s new Sleep Sensing & Home Automation Pad, a device that claims to do all of the above and more without you having to wear anything.

Nokia Sleep review: What you need to know

The reason you don’t need to wear anything is that the Nokia Sleep Sensing & Home Automation pad slots neatly underneath your mattress. Once there, it monitors your sleep quality, tracks your heart rate and even senses if you’re snoring throughout the night, all without you having to do a thing.

Whenever you open the Nokia Health Mate app on your phone, the Nokia Sleep automatically syncs via Wi-Fi, which enables you to pore over your detailed sleep stats while munching your muesli.

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The pad’s benefits don’t end there, though. On Nokia’s site, it explains how it also works with IFTTT to let you create “home automation” scenarios. In plain English, that means you can use the pad to detect when you get in and out of bed, and it’ll adjust the lights, thermostat and more, providing you have the necessary, compatible smart devices.

Nokia Sleep review: Price and competition

At £99.95, the Nokia Sleep doesn’t have a huge amount of competition in the way of sleep trackers you don’t wear on your body. The Beddit 3 Sleep Monitor (£129) is one such rival, which measures respiration, temperature, and room humidity in addition to the metrics logged by the Nokia device.

Alternatively, if you’re happy to wear a fitness tracker while you sleep, the Misfit Ray is undoubtedly the best option under £50. Bear in mind that it has no display or heart-rate monitor, though; for that, you’re better off opting for the Fitbit Alta HR (£99).

Nokia Sleep review: Performance and usability

As for the pad’s core functionality – sleep tracking – that’s tracked in impressive detail. Just like Fitbit’s fitness trackers, the pad offers insights into how much light, deep and REM sleep you have each night. Where it differs is that it also produces an overall sleep score, giving you a much simpler overview of the quality of your sleep.

This is calculated based on a multitude of factors including the total duration of your sleep and the time spent in restorative phases, along with other info, such as how much time you spent awake and how long it took you to fall asleep and get out of bed in the morning. The duration of sleep and amount of deep sleep account for the largest proportion of the score – if you get less than seven hours it’s impossible to score the perfect 100 – and other points are then lost and gained based on the aforementioned “sleep hygiene measures”.

How well does the Sleep pad work? It’s very difficult to comment with any confidence about accuracy but the results the Nokia Sleep pad produced were largely in line with what I expected to see. Indeed, when my Garmin Vivoactive HR, which I wore simultaneously, said I slept poorly, so did the Nokia Sleep. The timing of my phases of deep sleep also matched, more or less. So far, so good. Most impressive of all, though, was that the Nokia Sleep recorded an average resting heart rate almost identical to that logged by the multisport watch.

It’s remarkable that something buried under more than 20cm of foam or pocket springs can detect every beat of your heart, but the Nokia Sleep pad seems to manage it. By selecting the “Heart Rate” button for a particular night in the Nokia Health Mate app, it shows you your highest and lowest pulse, along with a line chart depicting its fluctuations throughout the night.

The app offers similar levels of detail for other measures, too. You can see the exact percentages of deep, REM, and light sleep you logged for any particular night, alongside the recommended figures for these different phases, much like Fitbit’s Sleep Stages feature. There’s also detailed info about how many times you woke up and how long for, along with how long it took you to fall asleep and get out of bed in the morning. Finally, one metric that might spark some debates between couples is the summary of any snoring “episodes” you had.

It’s evident the Nokia Sleep pad gives you more than enough stats to sink your teeth into but the app also offers guidance on how to improve your sleep scores. In truth, if you’ve ever read anything about sleep “hygiene” most of the pointers will come as little surprise. They include tips such as keeping your phone out of the bedroom, dimming the lights before going to sleep and trying to go to bed at the same time every night – things most of us know we should do but still fail to achieve.

Although it’s designed to only monitor one person (it only occupies around half the width of a king size bed), I did have some concerns about how well the Nokia Sleep pad would work in a shared bed. For the most part, these fears were quickly allayed, and the device still seemed to accurately record my sleep and heart rate, without my partner’s presence interfering in any noticeable way.

However, one morning when she stayed in bed for a lie-in, the app did add a chunk of time to my sleep log for that day. You can manually change the ‘Woke up at” time in the app if this happens, but it could quickly become tedious, especially if you have a drastically different sleeping pattern to your bedfellow. This, it appears, is the main downside to owning the Nokia Sleep compared to using a wrist-borne fitness tracker.

My only other gripes with the Nokia Sleep pad are fairly small ones. First, although it’s easy enough to slip under your mattress, the end to which the power adaptor connects contains a small, solid plastic box. It’s no more than 8mm thick and is fully contained within the device's soft fabric outer casing, but with your full body weight bearing down on it, over time it could leave an imprint on your mattress.

Second, the unit could absolutely needs some kind of power switch. Whenever you have to reset the Nokia Sleep, it requires you to unplug it from the wall, which if your wall sockets are somewhere difficult to access, will be a pain. Similarly, the only way to check the status of the sleep pad is via a small indicator light on the top of it, which again requires a significant effort (lifting your mattress) if you want to ensure it's working properly.

Nokia Sleep review: Verdict

It’s not cheap, but there’s very little else that can do what the Nokia Sleep pad does at £99. The purpose-built sleep tracker not only lets you go to bed without anything strapped to your limbs, but also goes above and beyond most wrist wearables in terms of the insights it provides.

Having said that, the Nokia Sleep pad works best when you sleep alone. If you regularly share your bed with someone else, you might decide the benefit of not having to wear anything is outweighed by having to manually tweak your sleeping hours in the Nokia Health Mate app.

Whether you really need such detailed insights is another point to consider. If you only want to know how long you’ve slept for each night, along with the amount of deep and light sleep then a the Misfit Ray can do exactly that and for only £50. Moreover, it’ll count your steps during the day, calories burned and can even be used to count lengths when you take a dip at the local pool.

In short, while there’s nothing awfully wrong with the Nokia Sleep pad, the novelty of some of the data it provides might soon wear off, making it difficult to recommend over fitness trackers that do the basics just as well.