I shall sleep for science!

Such was my proclamation and enthusiasm when I was pitched the idea of reviewing a sleep-monitoring gadget. Of all the activity trackers out there, surely the best kind is the one that doesn’t require any activity of you at all. And among them, the $129 Sense sleep tracker is rather unique in not requiring the user to wear anything extra while in bed. This system works with just a cute little sphere, barely larger than a tennis ball, positioned next to my bed and a tiny "pill" sensor attached to my pillowcase.

What could possibly go wrong? Quite a lot, as it turns out.

I really wanted to like the Sense sleep tracker for a number of reasons. Firstly, its creator is a young Londoner named James Proud, formerly one of Peter Thiel’s famous entrepreneurial fellows, and now the head of a company that’s raised $2.4 million from 19,000 people on Kickstarter and $10.5 million from Silicon Valley investors. That’s a lot of pressure to put on young shoulders and it’d be nice to say that his company Hello Inc. has an awesome product to justify that faith. But I can’t.

My other motive was selfish: I sleep terribly and needed some impetus to straighten me out. Alas, the Sense sleep tracker isn’t the solution to my problem for one simple reason: it just doesn’t work. It fails at its fundamental mission of tracking my sleep.

Here’s a typical Vladsleep scenario: Go to bed at 10PM, then spend an hour on the internet via either phone or Chromebook. Fall into fitful sleep. Wake up at 2AM, leave bed, do more internet stuff in other room. Return to bed around 6AM, and sleep for another couple of hours before work. On the internet. Here’s how it looks through the Sense system’s eyes: You slept soundly for nine hours. Good job, Vlad!

I don’t trust it and therefore I don’t respect it

The Sense sleep tracker isn’t convincing me to change my habits because it isn’t smart enough to earn my respect. It wants to be. Boy, it sure tries hard, offering measurements of in-room conditions like brightness, humidity, temperature, and even air cleanliness, but they’re all for naught because I never feel like the numbers it provides are precise. And, honestly, some of the information this systems spews out crosses the threshold of being condescending. I really don’t need to be told that a dark and quiet bedroom is more conducive to a good night’s sleep.

There are good things about the Sense system, many of them, but they’re all peripheral to a rotten core of inadequate functionality. The mobile app, which I tested on iOS but is also available on Android, is comprehensive and detailed. If it didn’t give me nonsensically high scores for nights where I’d absconded the bed for multiple hours, I’d consider it a good one! The design of the Sense ball itself is downright delightful, and it illuminates in various colors to signal conditions in the room or to act as a kaleidoscopic light accompaniment to the morning alarm.

I’m a big fan of two clever bits of technology in the Sense system: the ambient sounds designed to gently put you to sleep and the gradual alarm devised to equally gently pull you out of it. None of this is groundbreaking, but it’s super neatly executed. I use the app to set up relaxing white noise for a half-hour playback in the evening and then — on the occasions when I’m actually in bed at alarm time — I seriously enjoy the soft and polite way it wakes me up. Hello claims that the Sense ball is smart enough to know when I’m sleeping lightly, and it will wake me up sooner than requested if it finds an opportune time for it. Maybe that’s true, I don’t know; I just know that this thing is an awesome alarm clock.

Now, you might think that I’m a terrible test subject for a sleep tracker if I don’t do much sleeping, but I would argue that if the Sense ball was actually as smart as it aspires to be, it’d have very quickly shamed me into discipline. Instead, it kept rewarding me with false-positive scores like 86 out of 100, which discredited it in my eyes. Others have reported false negatives, with the Sense stopping tracking when they’ve had to leave the bed at night to go to the bathroom or tend to a child or pet.

Going to the bathroom might end your measured sleep prematurely

Hello does say that Sense is designed for monophasic sleep, which is a fancy way of saying it will only record one continuous sleep session per night. Polyphasic or scattershot sleepers like me are apparently excluded. I'd have liked to have the manual option of clocking in and out of bed — the Sense ball knows when it's pressed down to switch off the alarm, and the same gesture could be used by people like to me to announce weird sleep timings.

My unhappiness with the Sense system stems from how close it comes to being a sham. There are so many assumptions built into this little ball about the "typical" sleep that it really can’t accommodate even slightly odd patterns. Either you sleep a regular-ish eight hours during regular-ish times — in which case you might actually get reasonably accurate scores on the quality of your sleep — or you’re left staring at meaningless numbers, such as my last two nights, which were quite similar, but one got a 52 and the other got an 85. I'm aware that most other sleep trackers suck just as bad, but that doesn't excuse the Sense system's failures.

I wanted this beautiful, almost artful little ball of smart sensors to be great. I wanted it to fix my sleep by providing real smarts and insight into my atrocious sleeping pattern. Instead, it behaved rather dumbly, sticking closer to its expected timings than the actual activity I was engaging in. This is beautiful, almost artful technology, but it’s not smart. And as much as I like it as an alarm clock and a bedside decoration, I can’t endorse the Sense sleep tracking ball because it just isn’t very good at tracking sleep.