I was under the impression that iOS apps can only talk directly to Bluetooth Low Energy devices, not Bluetooth 2.1. Your Kickstarter page only mentions Bluetooth 2.1 support. What am I missing?

I would really like to know the answer to this, as well.

Scroll down to UIBackgroundModes:

http://developer.apple.com/library/ios/#documentation/genera...

Are you referring to bluetooth-central? That’s for the CoreBluetooth framework, which in turn is only for Bluetooth Low Energy:

http://developer.apple.com/library/ios/#DOCUMENTATION/Miscel...

No, I'm referring to "external-accessory". This works with both dock connector and Bluetooth iAP accessories. You're right that the other one is only for BT LE (4.0). It's understandable that many people are confused about the CoreBluetooth vs MFi Bluetooth.

if inPulse has the Apple MFI authentication part on-board, then yes, they can talk Bluetooth 2.1 to iOS devices, from a backgrounded app.

Thanks for the clarification. Congrats and good luck!