So you want to bring your own fitness gadget ideas to life? MetaHealth can help. It is a smart development board with Bluetooth, heart rate, GSR, and motion sensors for prototyping and research. It can be used to measure fitness, mood, motion, and temperature.
The board is powered by an ARM CORTEX CPU and a coin-cell battery. It connects to smartphones, tablets, and computers using Bluetooth. The board is fully compatible with MetaWear SDK. You can find out more about it on Kickstarter.