They’re a really interesting platform full of interesting sensors, some that you can get access to on existing hardware some you can’t. The tiny circuit board contains
- IR temperature Sensor
- Humidity Sensor
- Pressure Sensor (barometric)
It also has two physical buttons. It transmits over Bluetooth LE so is only supported by newer hardware, not my laptop sadly, but this mean you do get 100m range and a long battery life from the button cell.
A few weeks ago I spent some time riding in the Alps, where I managed to spend quite a long time talking to a geologist about the innacuracies of GPS measurements. I particularly wanted a portable way of measuring barometric pressure. This is always a relative measurement as it changes with the weather, but if you know your start height and could calibrate at various points along the route, say top of every known col. You could end up with a very accurate measurment of altitude gain.
Helpfully the iPhone application that TI provide also provides sample code for interpreting the data coming from the device. It’s a pretty neat little, inexpensive package of sensors for playing with.