Engadget - Remember that nondescript heart-rate monitoring belt we peeked back in June? Now you know the company that's tossing out purchase orders for 'em. Wahoo Fitness has just revealed that it'll soon be shipping its own branded version of the product -- dubbed BlueHR -- and at least for now, it'll work exclusively with the iPhone 4S. Why, you ask? The 4S just so happens to have Bluetooth 4.0, and this here belt happens to utilize that very protocol.