The iPhone 4S has a little-heralded feature that makes it unique among phones, at least for a while: It can talk to a new class of wireless devices, such as watches and glucose and heart-rate monitors.
The phone, which went on sale Oct. 14, is the first one to have a new type of Bluetooth chip that can connect using very little power. The chip uses so little power that it can go into devices that are powered only by a standard "button cell" or watch battery.
The industry group behind Bluetooth on Monday said these small devices will be labeled "Bluetooth Smart." More fully-featured devices like the iPhone that can communicate with them and with other, standard Bluetooth devices will be labeled "Bluetooth Smart Ready."
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