With the addition of Sprint and T-Mobile, 2D barcode company Jagtag has made its technology now available across the five major U.S. wireless operators, or almost 90% of mobile subscribers. Anyone with a camera phone can use it to access content embedded with one of the company's tags via text message, email or Twitter.

New York-based Jagtag says its 2D barcode system is unique in that doesn't require a user to download a reader application to their phone.

"Marketers and publishers can now go beyond 'smartphone only' mobile marketing and engage the other 75% of people who don't own a smartphone," said Jagtag founder and Chairman Dudley Fitzpatrick in a statement. The company says three-quarters of its users own regular cell phones.

Brands and retailers have begun to embrace 2D barcodes in direct marketing campaigns as a new way to deliver coupons, sponsor contests and promote product launches.

NBC Universal partnered with Jagtag earlier this month to promote its coverage of the Winter Olympics at the CES trade show. The effort included a sweepstakes users entered by snapping and sending in a photo of a custom Jagtag code on screens in the NBC booth. The tag also provided information about the Games and coupons for Olympics-related merchandise.

Jagtag's 2D solution has also powered mobile campaigns for Sports Illustrated, Dell, Toyota, and Yahoo.

Among Jagtag's major competitors is Scanbuy, whose 2D technology has been used in campaigns by marketers including Sprint, Volkswagen and Discovery Communications. The company's ScanLife application is compatible with all major carriers and on 80% of new camera phones sold in the U.S.

Google is getting in on the action, too. Last month, it launched 2D barcodes that local businesses can put up in their windows for mobile users with camera phones to scan to for reviews, store information and walk-in coupons.

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