This is a Bluetooth 4.0 module（Bluetooth 4.0 slave module）. Compared with Bluetooth version 2.0 and 3.0, it’s more advanced for its lower power consumption. You can easily connect your own project to the primary device of Bluetooth 4.0 by using this module. For instance, it can transfer the detected data which is about the information of your body to iphone for displaying or analyzing, then, help you better manage your physical condition.
Xadow is a though small but perfectly formed Arduino(TM) compatible board series containing several modules. It's a kit extremely suitable for space-sensitive projects such as wearable devices & arts designs, which have higher request on size, weight and flexible cascade connection.
You can find more modules here
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