The InCharge Auto BT is a simple device, both in form factor and function. Essentially, it features a 12-volt power connection on one end of a 4-foot cable and a male analog auxiliary audio connection on the other. You may be asking, "If one end of the cable connects to power and the other end connects to the car, where does my phone connect?" The answer is: wirelessly. That "BT" at the end of InCharge Auto BT doesn't stand for Brian Tong. It's short for Bluetooth and this unit uses Bluetooth HFP and A2DP/AVRCP to wirelessly receive audio from your handset to be output to your car's speakers via the aforementioned auxiliary audio connection.
Paring the InCharge Auto BT with your phone begins by pressing and holding the phone button located on the head of the auxiliary connection--the only physical control you'll find of the InCharge, by the way--until a flashing blue LED indicates the unit is in pairing mode, then initiating the pairing using the phone's menus. Once paired, the InCharge's phone button serves to answer incoming calls and terminate ongoing calls. I was unable to find a way to trigger my paired phone's voice command system for initiating a call and the simplistic InCharge Auto BT doesn't feature a voice command system of its own, so I was stuck physically manipulating the phone to dial--minus one point for driver safety.
I should note that the hands-free microphone that you'll use for calling is located on the head of the audio connection, so if your vehicle's auxiliary input isn't located on the dashboard--or otherwise in close proximity to your face--you won't be able to take advantage of the InCharge's hands-free calling features or easily access its single button. If your audio connection lives in your car's glove compartment or deep in the center console, you'll need to look for another solution.
When you're not actively engaged in or receiving a call, the phone button doubles as a play/pause button for the InCharge Auto BT's A2DP audio streaming feature, allowing users to start and stop their music and podcasts. Additionally, other phone sounds can be piped through the InCharge Auto BT, including turn-by-turn directions from your favorite navigation app.
Although you don't have to physically connect your phone to the InCharge Auto BT to make use of its features, you can connect to the unit for charging if you desire. Located on the head of the 12-volt connection is a powered USB port that outputs 10W (about 2 amps at USB's 5 volts), which should be enough to charge an Apple iPad if necessary, and more than enough for any smartphone you can throw at it. XtremeMac includes a 4-foot 30-pin dock connector to USB cable in the box for all of you iPhone and iPad users.
It doesn't do much, but one of the XtremeMac InCharge Auto BT's strongest selling points is that it's basically idiot-proof. If you can figure out how to plug into your car's auxiliary audio input, you're already most of the way through understanding everything this device does--no instruction manual needed.
On the other hand, one of this device's worst selling points is the price and that, well, it doesn't do very much to justify it. At an MSRP of $79.99, I'm more than a little sticker-shocked. I understand that things can get expensive when you slap a "Works with iPhone" logo on the box, but that price is a bit ridiculous. For what you pay, I'm going to want to see voice command at the very least (as is, you can only answer, but not initiate calls!). The advantages of replacing two cables with one cable are not lost on me, but the moment you plug their phone in to charge then you're back to having two cables dangling across your dashboard. I just don't see the point in paying almost $80 to have to most high-tech solution when a cheap car charger and audio patch cable do pretty much the same thing for less than $20.