In fact, near field communication (NFC) payments just might be a big part of Passbook.

Apple recently bought AuthenTec, a mobile and network security provider that specializes in security techniques that could help make the iPhone more secure, such as content security and fingerprint recognition -- a feature the security company sells to several computer makers and recently agreed to provide to Apple's smartphone rival, Samsung.

With high-tech security features on board, people are more likely to quickly get comfortable with the convenience of paying for things with their smartphones.

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