I'm installing a blue-tooth light switch that has live, bulb, neutral and ground. The light switch that's being replaced has 3 wires, black, white and exposed copper (I'm guessing that's neutral or ground). Should I just leave ground floating or join it with neutral when connecting it to the existing 3 wire set up?
You have an old-style switch loop configuration, with no neutral in the box, just hot, switched, and ground. This means that you'll have to take your "smart" light switch back and find one that does not need a neutral wire.