This is the Adafruit Feather M0 Bluefruit LE - an 'all-in-one' Arduino-compatible + Bluetooth Low Energy with built in USB and battery charging. The Feather will automatically switch over to USB power when its available. To make it easy to use for portable projects, 3., 7V Lithium polymer battery connector and built in battery charging means you don't need a battery, it will run just fine straight from the micro USB connector. We also tied the battery thru a divider to an analog pin, so you can measure and monitor the battery voltage to detect when you need a recharge. It also is supported in Mac OS X and Windows 8+. Adafruit Feather M0 with a BTLE module This is the Adafruit Feather M0 Bluefruit LE - an 'all-in-one' Arduino-compatible Bluetooth Low Energy with built in USB and battery charging. Bluetooth Low Energy is a hot, low-power, 2.4GHz spectrum wireless protocol Adafruit Bluefruit LE SPI Friend - Bluetooth Low Energy (BLE) Blueto Adafruit Feather M0 Bluefruit LE Feather Board Bluefruit LE, 3,3V/48MHz, MicroUSB, Compatible Con Arduino E Adafruit Feather M0 Built in USB so it has USB-to-Serial program & debug capability built in with no need for an FTDI-like chip This makes it excellent for use in portable projects that will make use of an iOS or Android phone or tablet.
