tōd smart beacon uses Bluetooth 4.0 to connect you to your surroundings
Bluetooth is one of those technologies that few people really consider as evolving at this point in time. Perhaps that's why there are devies being released with Bluetooth versions from 2.0 to 4.0 instead of everyone sticking to the latest standard. There are advantages to having the latest version, though, as 4.0 includes a feature that really changes how it can be used: low energy consumption.
The tōd (pronounced "toad") is a new accessory looking for funding on Kickstarter. Basically it's a tiny Bluetooth 4.0 beacon that can run for years on a button cell battery and is cheap. The idea is that you place these beacons all over the place, and by knowing whether or not the beacon is in range of your mobile device, you can make a lot of things happen.
The project page lists dozens of uses, and there are more uses to knowing when something is in range or not than you might think. The more basic ones that you can already achive on Android with apps like Tasker include, for example, entering car mode when in the car, having a beacon at work to let the device know you've arrived there, and so on.
Having the sensor separate from the phone can, however, do a lot more, like having one on your pet/child to let you know if they get too far away from you, or even putting one on every person in the family to let the others know if they're home/nearby.
The beacon can also be used for other things, like a wireless business card at a conference, or heck, it will even work as an online dating service and let you know if a potential love match is physically nearby. Developers can even make add-ons that connects to it and, for example, detects sound, moisture, or anything that you can turn into an electronic signal.
I've seen similar sensors before, but what makes this special is definitely Bluetooth 4.0. Running such a sensor for years on a button cell battery is amazing, and simply something you cannot do with older versions of Bluetooth or WiFi. When you can fit such a tag to a dog collar and leave it there without worrying about battery life, that's when such a sensor really has reached a new level of usefulness.
Unfortunately Bluetooth 4.0 means it's not compatible with a whole lot right now. The iPhone 4S, iPad 3, and Droid Razr are the mobile devices currently capable of using this. More will follow as manufacturers implement Bluetooth 4.0, and perhaps this finally gives them a reason to do so.
This is a Kickstarter project, though, so it does need help to get funded and go into production. The beacons are $32 each, and the project needs to raise another $42,000 in a little over a month. That might be doable with the iPhone 4S being one of the supported devices, and it would be nice to actually have this product available as more devices come out with Bluetooth 4.0, but if not I'm sure this will succeed at a later date when it's slightly less device-exclusive.[Kickstarter]