We initially expected the accessory to be announced at Nokia World last year, but this did not happen, in part because high-end Lumia devices were not Bluetooth Smart ready (i.e. enabled for Bluetooth Low Energy). This was rectified by the Lumia Black update and this, together with today's app release, means it is now logical to assume that the accessory will be formally announced at MWC at the end of the month.
Here's how we described the accessory when in our earlier reporting:
The tag, in conjunction with an app on the phone, can be used to track the location of items that it is attached to (e.g. a bag, or a set of keys), and the tag can also be used to locate the phone, if it is nearby via the digital equivalent of a "where are you" shout out (e.g. useful if the phone is hiding under a pile of papers on a desk).
The tag accessory works by having a constant connection with the phone, enabled by Bluetooth Smart. If this connection is interrupted (i.e. the tag goes out of range) the phone will record its current location via its GPS sensor. This information, which is displayed in an associated app on the phone, can be used to locate the tag at a later time (i.e. it will tell you where you have left your keys or bag). The same app is likely to be used to manage the sensor (i.e. pair it with the phone, and monitor battery level) and will almost certainly draw on Nokia's HERE Maps and LiveSight technology to display location information.
The Windows Phone Store entry for the companion app essentially confirms this description and adds some extra detail. Notably, the app can be set to provide a number of alerts if a tag is no longer connected to the phone (i.e. goes out of range). These include an alert on the tag itself, an audio alert of the phone, and a vibrate alert on the phone. The app also provides information of the battery level of any connected tag and it appears that it is possible for the app to trigger the tag to "play" an alert at any time.
Screenshots from the app's entry in the Windows Phone Store also make it clear that it will be possible to pair multiple tags with a single phone (e.g. one for your keys, one for your luggage). You will also be able to pin your favourite tags to the Start screen for easy access.
The app will also enable you to see the last known location for a paired Treasure Tag. The location is shown on a HERE Map, together with information about the address and the time that the tag in question was last seen. Toolbar buttons offer options to navigate back to or to use LiveSight (augmented reality) to pinpoint the location in question.
Windows Phone Store description:
Whether you’ve lost your keys, misplaced your gym bag or forgotten what street you parked on, Nokia Treasure Tag helps you keep track of your belongings with intuitive visual and audio guidance.
Simply put tags on the things you treasure most and install this app on your phone. Now if you leave something behind, you’ll know where it is.
Nokia Treasure Tag can be downloaded from the Windows Phone Store for free. The app requires Nokia Lumia Black.