Imagine - FitBit owners being able to tap each others' devices and virtually befriend each other. For instance, you meet a new person at a bar/park/concert(wherever) and you like each other. Noticing that you both have a fitbit device, you bump each others' fitbit devices and they both acknowledge the bump and show a smiley and a confirmation of having shared info. 

Later when you sync your device with your mobile phone, the following flow follows: