Often, he said, they built up a "device fingerprint" of the machines used to visit.

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But consider the token that Braintree is using: the fingerprint of your device plus your location plus a password.

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Apple is not the only company that recognizes the use of fingerprint and biometric interfaces in device security and mobile payments.

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Glossy products are legendary for attracting fingerprint smears, and this device's shell made it look as if we suffered from a sweating condition even after we'd dried our hands to the bone.

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PUFs are an innovative way of safeguarding individual chips from data theft by using the unique 'fingerprint' inherent in every semiconductor device to protect its encryption key, making it very hard to clone and thus reverse-engineer and compromise security microcontrollers.

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There's fingerprint readers, but they're often specific to the device or the platform, and sometimes limited to just a handful of tasks.

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Art Stewart, vice president of wireless products at sensor maker AuthenTec, which provided fingerprint sensors for the phone, says LG had "antenna issues" with the device.

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The projector itself is found on the very top of the device without any recession, which will likely make it a candidate for being a fingerprint magnet.

ENGADGET: Topic: Mobile