All iPod touches
All iPods newer than 4th generation
All iPod nanos
GPS-assisted iPhone FM transmitter
Finding stations is easier than ever
Charges iPhone while in use
No need for airplane mode
LCD screen is dim in daylight
iPhone app may not be necessary
FM transmitters for iPhones and iPods are tricky devices. While they're useful (especially as fewer and fewer cars sport tape decks), they also have drawbacks: interference-free stations are hard to find in densely populated areas, a station that works in one town may not work in another, and radio interference is common.
But many of those concerns are less serious with the Belkin TuneCast Auto Live iPhone FM transmitter, a device that makes it easy to listen to your iPhone in the car.
The Belkin TuneCast Auto Live plugs into your car’s power jack and runs a cord to the dock connector of your iPod or iPhone. On that cord is a remote control used to find clear stations and set favorites.
A key feature of the TuneCast Auto Live is that it leverages the iPhone’s built-in GPS to quickly and easily find the clearest station to transmit over (the device works with iPod models, too). Simply click the button on the remote and your iPhone will automatically be switched to the clearest station available. Just tune your radio to the same station and you’re all set.
While the minimum requirement for this feature seems to be the device itself, Belkin also provides a free iPhone app that interfaces with the TuneCast Auto Live. The app seems primarily to provide another interface for the device (though it also provides alternate suggested stations, while the remote only offers one; the remote generally finds the best station, but sometimes choosing one of the alternatives from the app will net better sound). So, while it seems a bit extraneous, it's not required and it's free, so no points off for that.
Even better, because the tuning of your phone to the best signal can be done with the remote, you never have to look at the iPhone’s screen. This makes driving and listening to your iPhone much safer than with devices that require you to take your eyes off the road more often.
Because they are often in competition with radio braodcasts, FM transmitters are prone to staticky interference or weak signals. While the TuneCast can't prevent all interference, it's certainly no worse than its competitors. It also offers three Pro settings that boost the strength of the signal and make it louder. The difference between the three is unclear to me, but the highest setting works so well I didn't need the other two.
It’s hard to understate how useful this device is. I’ve had many iPod and iPhone FM transmitters, but none of them have ever been great for everyday use due to interference or needing to put the iPhone in airplane mode to use (and thus missing calls). Now, though, I listen to my iPhone in the car all the time – and without worrying about missing calls.
Short of a direct connection from your car stereo to the iPhone (and while those are available, they’re expensive), this is one of the best options for sending your iPhone’s music to your car stereo that I've encountered. Many users with tape decks like tape adapters, which avoid radio interference and having to switch channels. While that is convenient, I've never had a tape adapter that lasted more than a few months without breaking, so those are less and less an option for me.
Given all this, any iPhone owner who drives a lot and wants to listen to music while also not being at risk of missing phone calls owes it to themselves to check out the Belkin TuneCast Auto Live.