Well, but ... It does not say clearly that the product documentation, where even descriptive, is that this "locator" will not really allow you to follow in real time the movement of an object. I think there is a "fuzzy marketing" (voluntary ???) product. In fact, the WS-10 sending its position to your phone (provided your Bluetooth is enabled on the smartphone, and the tracker is properly detected). If the tracker is outside a radius of about 40 meters, or not detectable because of obstacles, the application will ask you if you lost it. You click to open the application that will offer you display a map indicating "only" the last recorded position of the tracker WS-10. So interesting, as long as the tracker is in the reception range, the Bluetooth is active, the button battery (autonomy announced approx. 6 months) is not empty and that the tracker is not detached from 'desired object. Side configuration is really super simple: - Put the button battery in the WS-10, - Turn on Bluetooth on your Nokia Lumia, - Download the free application "Treasure Tag" on the Windows Phone Store, - After starting the application "Treasure Tag" you are asked if you want to add a locator, select your WS-10. You can give it a name, like "The bag of Loic" for example, and associate a representative icon of the object tracker. From the WS-10 Bluetooth sending its position Lumia. It is intended as a "tracker", but I was expecting a little better in terms of "location", especially Nokia. We will say that its worth 20 Euros, but then no more for the type of service rendered by this.