Samsung briefly mentioned its new Galaxy SmartTag alongside the new Galaxy S21 and Galaxy S21 Ultra models at Galaxy Unpacked, but there's a tiny detail that might have passed you by.

The Samsung Galaxy SmartTag will only work with Galaxy devices, meaning it's largely useless to the rest of the Android community or for those with Apple's iPhone.

That might come as something of a surprise, as Samsung has been pushing SmartThings quite a lot of late. It's via SmartThings Find that you'll be able to use the SmartTag, integrating with the SmartThings app and appearing alongside your other smart home devices.

SmartThings is Samsung's smart home platform. It's widely compatible with big-name brands in the smart home space, like Arlo cameras, Ring or Philips Hue.

It's designed to have universal appeal, giving you somewhere to build and control your smart home, rivalling similar interoperable services from the likes of Amazon's Alexa or Apple Home, with apps on Android and Apple devices.

I might seem silly, therefore, to not have your new tracker tag play its part in a system that you want to build. Instead, it's limited to Samsung Galaxy devices running Android 8 and higher - and Samsung tells us that there are "no immediate plans to support other devices."

If you try to connect to the SmartTag from a non-Galaxy phone, you'll get a warning that it's not compatible. You'll be able to detect it via Bluetooth, but you won't be able to pair with it. Even if you set it up with a Samsung phone, and then try to access it via another device using the SmartThings app, it doesn’t work.

The flip side of the equation is that Samsung is still the largest global smartphone manufacturer, so there are potentially a lot of devices that could use SmartTag, and a lot of users who could potentially find and locate lost devices too. Let's face it, just about every café or restaurant will have a Samsung phone in it, but if you're in a mixed-phone household, only the Samsung user would be able to detect the SmartTag.

We suspect that Apple will take the same approach with its rumoured AirTag. Apple is used to building behind its own walls and only serving its community, and the obvious problem here will be that Apple will use the Find My app which you only get on Apple devices.

For Samsung it's a different situation, because SmartThings is a universal platform - but there's one important detail. SmartThings Find appears to be limited to Samsung phones. It doesn't appear in the SmartThings app on other devices - and this is the interface you use to detect your SmartTag. When it comes to detecting devices, this is actually controlled by Samsung's Find My Mobile app and it's here, in the settings, that you'll discover the option for "offline finding", which is the part of the system that Galaxy phones will use to detect lost devices, which likely explains the limitation.

Of course there is a solution to this problem: get a Tile. Tile has a range of devices at different price points and has essentially built and dominated the Bluetooth tracker market up to this point. It also works both Android and iPhone, without the limitations that other brands like might encounter.