Hands On With Cadillac's OnStar 4G LTE

The 2015 Cadillac ATS Coupe starts at $38,000 and is available with either a turbocharged 2.0-liter four cylinder or a naturally aspirated 3.6-liter six-cylinder engine.

For this hands on, we'll focus on the built-in OnStar 4G LTE, an always-on, fast cellular data network that powers the car's infotainment and navigation systems—to a point. Note the new emblem style; this is the first Cadillac with it.

OnStar 4G LTE has several main purposes. First and foremost, it turns the car into a roving cellular hotspot, with AT&T 4G LTE connectivity for up to seven devices in a 50-foot range.

I connected my iPhone 5s via Wi-Fi to the car's hotspot with no issue, and was able to pull down 5Mbps, with 1Mbps upload speeds, inside the building.

A 4G LTE stream of a 720p YouTube video also looked sharp and clear on the iPhone.

RemoteLink runs faster and more reliably now that the car has integrated 4G LTE.

We tested RemoteLink by looking up a destination on the phone and sending it to the car. It took less than 10 seconds to do so.

The on-board navigation system otherwise works normally as before.

Unfortunately, OnStar 4G LTE doesn't power the built-in services already in the car, such as Pandora, which is a bit surprising—to use the Pandora link on the main menu, you still have to connect your smartphone.

OnStar 4G LTE does provide some services, though, such as weather reports (pictured).

XM Radio still requires an extra cost subscription. How many different monthly fees are you willing to pay just for your car? That is the question GM is waiting to have answered.

RemoteLink can tell you how much fuel the car has left, how far you can drive, and (importantly) the status of your engine oil.

You can lock and unlock the car, start it, blow the horn, and turn on the lights from afar. Fun for the whole family!

This is the RemoteLink interface for looking up destinations and sending them to the car.