One of the most powerful new features in iPhone OS 3.0 is also its least discussed: Bluetooth 2.0, more specifically, the A2DP (a.k.a. stereo Bluetooth) profile. A2DP allows an iPhone running 3.0 to transmit stereo audio to a Bluetooth receiver -- enabling an entire category of stereo BT headphones to work with the iPhone.
A2DP allows the use of stereo Bluetooth headsets with your iPhone. You can listen to the iPod application and even use it for phone calls -- including Skype. It can also be used to transmit audio to compatible BT car stereos.
I've been testing the new CERULEAN F1 ($99, pictured) stereo Bluetooth headset from iSkin and I'm impressed by the sound quality and its ease of use. I was initially relegated to using the F1s with my Android-powered G1 phone because the iPhone lacked A2DP. I began testing the F1s with iPhone when OS 3.0 was distributed to developers.
I have to admit to being skeptical initially about stereo Bluetooth because of the audio problems and dropouts that plagued many of the early Bluetooth headsets. Boy, have we come a long way since then. Audio quality is good and clean with the F1s and I was able to walk almost 20-feet away from my iPhone before I got my first dropout.
The battery is estimated at eight hours for music, but I haven't yet run into that limit yet because I've been using the F1s mostly while working out and bike riding -- where they really shine. If you don't like dealing with cables and having to be tethered to your iPhone, BT headphones are an indeal solution.
The Type A ("micro") USB port on the F1s is a minor annoyance (I'd prefer mini USB) but now that it's a pseudo-standard for charging mobile phones, its here to stay. I'd also like it better if the cable that connects the two earpieces came out of the bottom, but other than that I have little bad to say.
Sound quality and range make the CERULEAN F1 a great companion to the iPhone, especially if you want to jam cable free.