This new Proto Board is designed for you to get started easily. You can power your Nano via USB, coin cell battery or rechargeable battery (this board does not have battery charger circuit). The top part could be removed if you don't need it. It has 3 connectors for Seeed's Grove modules (more details below). Last but not least, we have reserved a place for the Apple MFi authentication coprocessor; you can develop BLE HomeKit product if you have the MFi license.