Sprint calls its new Spark service, which they started implementing last year, a “super-high-speed capability” network. It’s faster than the 4G LTE network that they’re still expanding nationwide, but is a Spark-compatible phone something that you should look into? Well, that depends: how many things do you do on your phone at once?

Another way to put that question: how often do you use your smartphone as a phone? Spark is now available in New York City, so our super-smart-engineer colleagues down the hall at Consumer Reports tested the network’s capabilities. While their tests on the network’s speed and reliability aren’t finished yet, they can tell us one thing: Spark phones aren’t able to maintain a data connection and a voice connection at the same time, unlike the current 4G LTE network.

That’s not necessarily an argument against buying Spark phone, but there are a few situations where you might want to run an app that requires data while you talk on the phone. Let’s say you’re driving to a friend’s new house using your phone’s GPS app, get lost, and give them a call (handsfree, of course). According to Consumer Reports’ tests, you’ll lose your access to the GPS app while you talk on the phone.

Sprint’s Spark data network fizzles during voice calls [Consumer Reports]

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