Unlimited data plans are back. But are they needed?

Unlimited data plans aren't necessary for most smartphone users, because they don't hit the 2GB per month data cap, according to a study by NPD Connected Intelligence. So will new unlimited data plans from several carriers cause a splash?

T-Mobile (and Sprint, and MetroPCS) made a stir by announcing new, unlimited individual data plans priced from $70 to $90 per month, including unlimited calling and texting.

That sounds wonderful, but for most people in the U.S., it's also irrelevant.

That's what data on smartphone usage by research firm NPD Connected Intelligence indicates. The company has installed an app on 1,000 Android smartphones of volunteers to track how much data people consume each month. Though iPhones aren't included, analyst Eddie Hold told TechNewsDaily that iPhone usage is pretty similar and that they will begin collecting information from iPhones in the next few months.

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TechNewsDaily was the first to see NPD's latest data for July. And the numbers make it hard to see why most people should fret about data caps. The overwhelming majority of customers on AT&T, Sprint, T-Mobile and Verizon don't even use 2GB per month, which is below the data caps for all but the stingiest plans from all carriers for the common two-year contracts. And virtually no one uses over 3GB. (Sprint is the one carrier that has already been offering unlimited data plans.)

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T-Mobile, however, does have the most data-hungry users, according to NPD. Eleven percent of customers use more than 3GB per month, versus 4 percent for AT&T and Sprint and 3 percent for Verizon.

"T-Mobile consumers tend to be younger," said Hold. "Younger demographics are the ones we find hit the network harder by doing a little video and music streaming."

And even when customers have had unlimited data at their fingertips, as on Sprint, most didn't take advantage of it. "In general, Sprint's usage is the same as the other networks and less than T-Mobile," Hold said.

One reason people stay under their limits is that they often use their smartphones over Wi-Fi. And even if people use only the cellular network, they will probably be fine. For example, 2GB per month is enough to do all the basics, such as email, Web surfing and Facebook posting, as well as streaming music for 30 minutes per day.

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