WTF is... Bluetooth 4.0?
It's in the iPhone 4S, but does it matter?
Apple's iPhone 4S, which went on sale last week, is the first phone to support version four of the Bluetooth standard. That makes it something of a flag-waver for the technology. But with most users happy to make do with Bluetooth 2 - Bluetooth 3 is out but seemingly little used - does this matter? And what the heck does Bluetooth 4 do anyway?
The 2.4GHz Bluetooth wireless standard has been around for quite a long time now - developer Ericsson released the first spec in 1994. It has since found favour for hands-free headsets and wireless headphones. It's used to send files short distances and to connect mobile phones to other devices as modems. But not all devices support all the available Profiles - the standard's formal definitions of specific applications.

Apple's iPhone 4S is the first of many smartphones to include Bluetooth 4.0
Versions 1.1 - the first Bluetooth release to be stamped as an official standard by the IEEE - and 1.2 provided the device discovery system most users of Bluetooth devices are familiar with, allowing gadgets to be paired, typically by entering a preset or user-created code number. These versions also defined a data transfer speed up to around 721kb/s.
Bluetooth 2.0, released in 2004, upped the real-world peak data rate to 2.1Mb/s, using the Enhanced Data Rate (EDR) option. In 2007, version 2.1 added simpler methods for pairing devices, for example allowing a computer to display a number, which you then enter on the phone. It’s also the version that allows other mechanisms to be used for pairing: tapping two NFC devices together, for instances.

Not that Apple does any more than mention BT 4.0 in the spec sheet
Bluetooth 3.0 added the ability to use other wireless systems, such as Wi-Fi, for data transfer, a technique enshrined in the standard in 2009. Bluetooth establishes the connection then routes the data over Wi-Fi, as the High Speed (HS) option. It was to have supported ultrawideband (UWB) too, but that never made it into the standard. BT 3.0 is supported by some phones, but is perhaps best regarded as a solution looking for a problem to solve.
Bluetooth 4.0, which was release in June 2010, adds a couple of key extras. Firstly, it increases the range of the Bluetooth radio, though how useful that will be remains to be seen in such a congested band. More importantly, it adds a whole new class of functionality under the banner of Bluetooth Low Energy - and in doing so, slips a Nokia technology into the iPhone 4S and Apple’s most recent Macs.
Low-power radio systems aren’t new. Systems like Garmin’s ANT+, Z-Wave and Zigbee all overlap to different degrees with some of the functionality claimed by supporters of Bluetooth 4.0, such as medical monitoring, home automation and appliance control.
Next page: Bluetooth goes fourth
COMMENTS
file transfer?
File transfer? Over bluetooth! Hey, about time - that would come in handy! I quite often take a photo on my iphone I want to bluetooth to a friend, so that would be useful.
Ah wait, I remember.. in the dim and distant past (before I went iphone), I was able to do this with my Nokia's and Sony Ericsson's..
Apple - striving to ensure you eventually forget about the freedom you once had.
Hopefully it's better than Apples old Bluetooth support.
As nothing (Android, Nokia, SE) could send anything to an iPhone or receive anything from an iPhone over Bluetooth last time I tried. However Iphone to iPhone worked fine unsurprisingly...
Seems like Apple like to even engineer their products with intentional interoperability problems to try and force more iPhone sales..
It's quick and simple
I use it a fair bit; only a couple of weeks ago, I was entertaining a gentleman caller and the simplest way to get the photos he'd taken was to send them via Bluetooth from his HTC to my Nokia; quick, very easy, no need to wait for slugging spam filters and internet connections to do their work. And no chance of anyone else seeing the pictures, either.
If I take snaps when out and about on my phone, again, it's simple and quick to just send them by BT to the laptop.
Sometimes I don't want to fiddle around uploading to a website, setting privacy options, and so on. I just want to get a picture or pictures from one device to another, easily and quickly. And Bluetooth, on many devices, is actually jolly good for doing that.
Security Settings
BT has a "High Security" setting which forces the device to do "device pairing" before being able to connect to the other device. Some smartphones are even locked into said mode for security reasons.
You mean the iPhone can't do that?
OBEX is still part of Bluetooth 4.0, Apple.
The air-interface is only one part of the standard.
But hey, I just love to use my data allowance to email media files from my phone to an iPhone owner who's standing in front of me. It's the future, etc., etc.
Somewhat schizophrenically, Apple's implementation of Bluetooth on OSX is really top-notch.

