If you are looking for a freeware utility to keep an eye on the Bluetooth devices near you then you can try out BluetoothView. BluetoothView is a simple free utility which runs in the background and informs you about all the activities about your bluetooth devices. The good thing is that BluetoothView does not require any installation and you just need the single executable file and a Bluetooth Dongle to run it.
BluetoothView can be used to know information about the other devices in your house. This can be used to track your other family members. BluetoothView displays a lot of information about the Bluetooth devices which include Device Name, Bluetooth Address, Major Device Type, Minor Device Type, First Detection Time, Last Detection Time etc. BluetoothView works with Windows XP SP2 and Windows Vista.