If your device is Bluetooth Smart Ready then it’s compatible with Bluetooth Smart and Bluetooth but if it’s Smart then it’s not compatible with regular Bluetooth. Got that? Good.
The Bluetooth SIG, never content to leave well enough alone, as introduced three new “icons” for their new 4.0 standard. “Best” Bluetooth devices will support both “old” Bluetooth and 4.0 while Smart devices will only support 4.0. In short, Smart Ready devices will support dual modes and work the way with which we are currently familiar in devices like laptops, phones, and PCs, while Smart devices will support ultra low power devices like heart rate monitors and pedometers, allowing Bluetooth to come up against wireless standards like ANT.
Does this effect you in any way? Probably not except that “Smart Ready” phones will be able to connect with your workout gear. Otherwise, this is the same old Bluetooth you know and love except that 4.0 allows for reduced power consumption because the connection “pulses” rather than maintain a constant connection. It’s available now on the 4S and the new MacBooks.
So when you think of Bluetooth, think of “Smart” as “not really Bluetooth, but Nike will support it soon” and “Smart Ready” as “I can connect my heart rate monitor to this and it takes less battery.” Bluetooth is, well, still Bluetooth. You can read a bit more here, but now you know and knowing is, as we all know, half the battle.