You can also call any of your earlier-designated contacts by name, assuming Glass is connected to your phone as a Bluetooth headset.

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The TomTom go 700 SatNav unit (which now tops the TomTom go line), unveiled at CeBIT, provides hands-free communication via Bluetooth link to your phone, much as your Bluetooth headset would.

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The concept Simeonov shows here would be the high-end version with full LTE connectivity that could operate as a stand-alone phone replacement with a suitable Bluetooth headset.

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Two companies have recently been demonstrating a new type of mobile-phone headset they hope will challenge Bluetooth by supporting existing mobile phones and cordless home telephones.

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This vision is a play on convenience through miniaturization, like a Bluetooth headset freeing your hands from the phone.

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Think of the Bluetooth headset: it's a really sensible way to use your phone without having to take it out of your pocket so sensible that there's really no reason not to keep that headset in your ear most of the time.

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Then, when you finally get around to using the Bluetooth kit, there's usually the tricky process of "pairing" a phone with a headset, which isn't always clear--especially for first-time users.

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