Feather is the new development board from Adafruit, it's thin and light.The Feather boards, was designed to be a new standard for portable microcontroller cores.
To make it easy to use for portable projects, we added a connector for 3.7V Lithium polymer batteries and built in battery charging. You don't need a battery, the Feather board can be powered from the micro USB connector.
You can program all the Feather boards with the Arduino IDE.
The Raspberry Pi 3 Model B is based on the characteristics of its predecessors, but there are two giant upgrades:
The first is a next generation Quad Core Broadcom BCM2837 64-bit ARMv8 processor, making the processor speed increase from 900 MHz on the Pi 2 to up to 1.2GHz on the Pi 3, the second giant upgrade (and this is the one we’re personally most excited about) is the addition of a BCM43143 WiFi chip BUILT-IN to your Raspberry Pi. No more pesky WiFi adapters - this Pi is WiFi ready. There’s also Bluetooth Low Energy (BLE) on board making the Pi an excellent IoT solution (BLE support is still in the works, software-wise)
If you want your Arduino to transmit data with other device or control PWM, I/O pin, serial communication of the Arduino by PC or phone client. Trust me, you definitely don't want to miss it- our Elecrow ESPduino! It will help you a lot and save your time on the connection. It combines a Arduino UNO with a serial WiFi and can be apply on lots of project of IOT, such as Smart Home, Smart robot, Security system. The same size with more powerful function, this two in one board will give you surprise!