For buildings that require additional security, like government offices, the keys can be combined with other forms of authentication, such as PIN numbers or biometrics.

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The banks have also been experimenting with more sophisticated forms of user authentication, including fingerprinting, iris-scans and biometrics.

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The Biometrics assure the iWatch wearer is the authenticated user and provides an additional layer of authentication, which could be very important across the board from enterprise to personal security.

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