Hi Allen Rhodes,
We actually looked into this a bit early on in the project. Technically the band could connect as a Bluetooth headset with only a microphone, and the Bluetooth standard allows for that. It turns out that a lot of cellphones do not support Bluetooth headsets that are only microphones, once we tell the phone that we are only a mic, our connection gets shut down by the phone.
The lack of support from cell phones combined with the engineering effort that would have been needed to pull it off meant that we didn't investigate it further.
I agree that having the mic record into a custom app of the user's choosing would be super cool. When I'm on Windows Phone I can just use Cortana, but when I am testing out on Android or iOS I miss the functionality of being able to quickly jot down a note.