SendStation's smartCharge is yet another accessory for powering (and, thus, charging) your iPod shuffle in your car. However, unlike simple accessory-jack-to-USB adapters (such as Griffin's $25 PowerJolt), the smartCharge includes a pivoting "dock" for the shuffle. You plug the smartCharge into your car's accessory jack (a.k.a., cigarette lighter socket) and then plug your iPod shuffle into the USB port at the other end; the back of the smartCharge offers support for your shuffle, but still allows access to the shuffle's Off/On/Shuffle switch and battery-level button. A small light indicates power, and a built-in fuse protects your iPod from power surges.
The smartCharge's "dock" section rotates to let you position your shuffle at a better angle for viewing and pressing its buttons. Unfortunately, this rotation is limited to 36 degrees in each direction: If you've got a vertically-mounted accessory jack, these 36 degrees are enough to lean your shuffle back a bit for a near-perfect position; however, if the jack is mounted horizontally or diagonally, as it is on most cars I've seen, the smartCharge doesn't pivot enough to place your iPod upright and accessible. You end up having to rotate the entire smartCharge body 180 degrees in the accessory jack and then pivoting your shuffle down; this results in the shuffle being positioned at a better angle, but upside down. If the smartCharge allowed you to rotate its dock section at least 90 degrees in each direction (preferably more), it would be a more versatile product.
Another nice feature of the smartCharge is that it provides an audio-output jack for connecting your shuffle to your car stereo or FM transmitter. Because the volume level of the shuffle's USB port is affected by the shuffle's volume control, this isn't a true line-level output, but the jack is nonetheless convenient: Instead of having to plug/unplug both the shuffle and a cable, you simply plug your shuffle into the smartCharge and press play. (Unlike DLO's TransPod shuffle, the smartCharge doesn't include an FM transmitter, but it's also half the price.)
The only other issue I found with the smartCharge is that its body gets quite hot during use. In my testing, I didn't experience any problems with the smartCharge or my iPod shuffle due to this heat, but it's worth nothing.
Finally, the smartCharge's design is quite attractive as far as car chargers go. If your car's accessory jack is in the right position -- or if you don't mind an upside-down shuffle -- the smartCharge is one of the better car chargers we've seen.
(Note: The smartCharge can also be used with other USB-chargeable iPods by connecting Apple's USB dock connector cable to the smartCharge. However, when used this way, the smartCharge's audio output does not provide an audio signal.)--Dan Frakes
Car charger for iPod shuffle.