For chronically forgetful folk who are always losing their keys or wallet, it's not hard to find trackers that beep and buzz to help locate them. What's slightly harder to find though are trackers that don't get in the way during normal use, before you lose the thing it's attached to. Sydney startup HButler claims its new Orbit Card is the world's thinnest Bluetooth tracker, and New Atlas went hands on to test its tracking prowess.

The title of "world's thinnest Bluetooth tracker" turns out to be a contentious one, with plenty of companies planting their flag in that claim. But just looking at the numbers, HButler appears to be the rightful owner.

The Tile Slim is a chunky 2.4 mm thick, about the size of two credit cards. The Chipolo Clip is a reasonable 1.8 mm, and the recently-crowdfunded KiwiCard comes in at 1.5 mm. The Orbit Card, meanwhile, sits at a slender 1.2 mm. That's slightly thicker than the average card in your wallet, but it's hardly noticeable.

Thinness aside, the real question remains: how well does it do its job of helping you find your stuff? Well, that depends on where you most often leave said stuff behind.

The first step is to download the Orbit app onto an iPhone or Android device, and pair the Card with the device via Bluetooth. We found setup to be quick and painless, just a case of adding a new Orbit to the list in the app and holding down the button on the Card until they sync up. Then, any time it needs finding (along with whatever valuables it's tucked into), the app is opened and the big orange "Find Orbit Card" button pushed to start it singing out.

In our Hide 'n' Seek tests, we found a pretty powerful speaker crammed into that thin little card. Its cries are loud enough to be heard from across the house, and if you're in the same room you'll have no trouble digging it out. Inversely, if it's your phone that's always going AWOL, you can give the button on the Orbit Card a quick squeeze to call it.

If you have a habit of leaving stuff behind, the system has the option for a separation alert, causing both the phone and the Orbit to let out a shrill if they ever get out of Bluetooth range of each other. And it's as frustrating as you'd expect: getting up to make a coffee without both parties present was an office-wide announcement, and on a few occasions the phone and Card threw a tandem tantrum even though they were both still sitting in the same pair of pants.

In anticipation of this annoyance, HButler has added a Safe Zone option that calms that extreme separation anxiety when the phone is connected to a selected Wi-Fi network. But the downside with this function is that if you then leave the Safe Zone without the Orbit, the phone won't bother to sound an alert. The same is true if the phone is left behind in the Safe Zone, but the Card moves out of Zone range – not a murmur from the Orbit. Worse still, only one Safe Zone can be set at a time, rather than designating both home and office as screech-free zones.

In our experience, you're better off without the separation alert, and just using the Orbit system to ping your phone or wallet when you absent-mindedly leave one or the other around the house.

For longer distance losses, the app has a last-seen location map that shows where the Bluetooth connection cut out.

While it won't help with chasing down a pickpocket with real-time tracking, it can let you know where to start the searching if you aren't sure if you left your purse at the cafe, grocery store or friend's house. Once there, it's back to simply pressing the button to make it squawk to reveal its hiding place.

That said, HButler has announced that a future update to the app will introduce a service called Orbit Net. When that rolls out, the GPS coordinates of a lost little Orbit will automatically update whenever it comes into Bluetooth range of any other device with the app installed. Only you will be notified, too: it doesn't bother telling the owner of the device that found it, which is a nice little security measure.

There are a couple of other little cherries on top. The button on the Orbit can be used as a selfie remote, and the battery seems to be less of an issue for the Orbit Card than for other trackers. Some use replaceable watch batteries while others need to just be thrown out when the juice runs dry, but the Orbit Card can be recharged with a USB-powered clamp. HButler claims the Card only needs to be charged up every three months or so, but given our limited window, we didn't get a chance to verify this.

In the end, the Orbit Card mostly does what it promises – helping to find the wallet that you swear was in your hand two seconds ago – although we'd recommend switching off the separation alert. As the thinnest Bluetooth tracker out there (for now), the Orbit Card can be just stashed away in a wallet or purse and forgotten about. But when needed, it'll sound off to save the day.

The Orbit Card is available now for AU$49.99 (US$39.99), with discounts for larger orders. If you're always losing other things, like your keys or glasses, there's a range of other types of Orbit devices as well.

Product page: Orbit Card

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