Sniffing Out Consumer Bluetooth 4.0 Devices

There are few consumer devices that use BT4.0 and I would like to be able to pair them with Arduino over the Bluetooth 4.0/SMART/BLUNO etc.

In particular I would be interested into Leica Disto 110 laser rangefinder with 1.6mm accuracy and Measy RC16 Bluetooth 4.0 Keyboard & Air Mouse.

None of these devices have an Arduino APIs or libraries. How possible is sniffina and reverse engineering the commands, just on the BT4.0, so one can use these devices with Arduino?