Feather is the new development board from Adafruit, and like its namesake it is thin, light, and lets you fly!
We start with the first 6 boards pinouts:

Feather 32u4 Basic Proto
Feather M0 Basic Proto
Feather 32u4 Adalogger
Feather M0 Adalogger
Feather 32u4 Bluefruit LE
Feather M0 Bluefruit LE