Bluetooth Firewall
http://www.fruitmobile.com
FruitMobile Bluetooth Firewall protects your android device against all sorts of bluetooth attack from devices around you. It displays alerts when bluetooth activities occur. You can also scan your device and detect apps with bluetooth capabilities.
Bluediving (http://bluediving.sourceforge.net
Bluelog (http://www.digifail.com)
Blooover II (https://trifinite.org)
Btscanner (https://packages.debian.org)
BlueRanger (http://cyborg.ztrela.com