The Bluetooth Special Interest Group has announced a series of "Smart Marks" logos to denote compatibility with a new low energy specification that's been added to the much-delayed version 4.0 of its technology. Devices with the Bluetooth Smart moniker, such as digital thermostats and smart watches, are designed to gather a single, specific piece of information and can only connect with Bluetooth Smart Ready electronics, like the iPhone 4S. For example, this would allow an app to change the temperature in your house, or compatible watches to function like Fitbit or Nike+ devices. However, Smart Ready gadgets aren't limited to the low energy protocol — they still work with "regular" Bluetooth.
At this stage, Bluetooth 4.0 devices are few and far between, but of course, that will change as the standard matures. We're not sure if Smart Marks actually makes things simpler to understand, but luckily, SIG has a chart to help you sort it all out: