The Chronos is a little puck which can be connected to the back of an old watch, giving an analog timepiece smart features.
Connecting to an iOS app over Bluetooth (Android support is coming soon), it offers activity tracking functions thanks to a built-in accelerometer, as well as featuring an LED and vibrate alert for phone, email and message notifications.
There are other more nuanced controls, such as music playback functionality and the ability to hunt down a lost phone. These are based on gesture motions, taping the old watch's crown or face which the accelerometer then translates into specific commands.
That'd need some particularly sensitive and accurate motion tracking, so it'll be interesting to see just how well they work.
Back to the future
When notifications do come in though, you'll be able to customise the LED and vibrate patterns between 56 different combinations, pairing them up to selected notifications to help you identify them more easily.
Water resistant to an IP67 rating, the Chronos will be able to withstand a splash of water or two - just make sure your watch can, too. A USB charging base lets you charge the Chronos without removing it from your watch, with battery lasting a two day average.
As for actually connecting it to your watch, that's done with a simple suction adhesive pad, which can easily be pulled off and used on another watch should you swap out your timepiece. Have a wide enough bracelet and it'd probably stick to that too, should you not be a watch-wearer.
After a successful crowdfunding campaign, the Chronos is now available for general order, ready to be shipped in early November. It'll set you back $99.99, which is around £82, or AU$130.