US homes have more than a half-billion Internet-connected devices

A digital milestone of sorts has been reached: the continuing addition of smartphones and tablets to U.S. households means there are now more than a half-billion home-based devices connected to the Internet, and the combination of smartphones and tablets now exceeds the "installed base of computers," according to a research firm.

"Overall, the number of connected devices per U.S. Internet household has grown to 5.7, up from 5.3 devices three months ago," says a new report from NPD Group's Connected Intelligence.

"PC penetration among U.S. Internet connected households is nearly ubiquitous at 93 percent, but virtually unchanged over a three-month period. "

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