Adafruit Feather M0 Bluefruit LE

Key Features: Adafruit Feather M0 with a BTLE module ATSAMD21G18 ARM Cortex M0 processor(clocked at 48 MHz and at 3.3V logic, same one in the new Arduino Zero 256K of FLASH (8x more than the Atmega328 or 32u4) and 32K of RAM (16x as much) Built in USB so it has USB-to-Serial program & debug capability built in with no need for an FTDI-like chip 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. In particular, it's the only wireless protocol that you can use with iOS without needing special certification, and it's supported by all modern smart phones. This makes it excellent for use in portable projects that will make use of an iOS or Android phone or tablet. It also is supported in Mac OS X and Windows 8+.To make it easy to use for portable projects, 3.7V Lithium polymer battery connector and built in battery char