Bluetooth 4.0: What is it, and does it matter?

The recently announced iPhone 4S comes with Bluetooth 4.0, which is a first for mobile phones. What exactly does Bluetooth 4.0 mean, and what advantages does that give the iPhone? CNET answers these questions and more.

Nicole Lee Former Editor
Nicole Lee is a senior associate editor for CNET, covering cell phones, Bluetooth headsets, and all things mobile. She's also a fan of comic books, video games, and of course, shiny gadgets.
Nicole Lee
2 min read

One of the lesser-known facts to emerge about the iPhone 4S yesterday is that it is the first phone to launch with Bluetooth 4.0, the latest version of Bluetooth. Not many products are available with Bluetooth 4.0 just yet--in fact, two of the most recent products to ship with Bluetooth 4.0 are also from Apple: the MacBook Air and the Mac Mini. Bluetooth 4.0 is backward-compatible with all other versions of Bluetooth, so you can pair existing Bluetooth headsets with the new iPhone without a problem.

Apple iPhone 4S
The Apple iPhone 4S is the first phone to ship with Bluetooth 4.0. Apple

So what's so special about it?
According to Mike Foley, executive director of the Bluetooth SIG (Special Interest Group), the key new feature of Bluetooth 4.0 is its low-energy technology. This lets device manufacturers replace proprietary sensor technology with Bluetooth, which is a more widely adopted standard. An obvious example is in the health and fitness category. Most pedometers, heart rate straps, and blood glucose monitors are designed to only talk to a specific wristwatch or control unit. If these same devices had Bluetooth 4.0, they could speak to any Bluetooth 4.0 device, be it phone or computer, without requiring an intermediary.

"It's an extremely optimized version of Bluetooth," Foley said. "It enables an entirely new class of product into the Bluetooth world."

This version of Bluetooth is thus targeted specifically for small battery-operated devices like Nike+ sensors, Fitbits, and similar products that require almost no power. Foley envisions that gyms and fitness centers would have Bluetooth-enabled computers so that you could automatically upload your fitness stats to the cloud after you finish your workout, for example. The first such device is a Dayton heart-rate chest strap using a Bluetooth 4.0 chip from Nordic Semiconductor.

Other potential uses of Bluetooth 4.0 include standardizing active 3D glasses so you don't need line-of-sight for them to work, and possibly a wireless payment system similar to NFC.

Do I really need it?
It's still early days for Bluetooth 4.0. As we mentioned, the iPhone 4S is currently the only phone to have this specification, and there aren't that many Bluetooth 4.0 devices yet to make use of the technology. Still, we should see more Bluetooth 4.0-compatible products before the end of the year, with more phones adopting the standard as well. Hopefully developers will get on board to create custom apps to take advantage of Bluetooth 4.0 accessories. We wouldn't rush out to get the phone just based on this one specification right now, but it might be a big deal in the future.