Arduino Derivative Boards

'Arduino-Based' boards are boards that have been designed and built using the Arduino footprint, and / or the Arduino bootloader. They can usually be programmed via the Arduino IDE. Just because they're not made by Arduino themselves doesn't mean that they're illegal copies. Quite often 'clone' boards are supported by Arduino - It's all part of the 'Open Source' movement. Arduino-Based boards usually offer functionality or performance levels that Arduino have not chosen to offer in their genuine boards. Occasionally, they're even cheaper.

Pololu Derivative Boards A-Star 32U4 Micro Dev Board
Freetronics Derivative Boards EtherMega

EtherMega

£95.20
Pololu Other A-Star 32U4 Mini SV
Pololu AVR Processor Based A-Star 32U4 Mini ULV
SparkFun Kits Digital Sandbox
Freetronics Derivative Boards EtherTen Sold out

EtherTen

£59.95
Freetronics Original Boards LeoStick (Arduino Compatible)
Seeed AVR Processor Based Seeeduino Stalker v3
Seeed Derivative Boards Seeeduino v4.2
SparkFun Zigbee Teensy 3.1 XBee Adapter
SparkFun Derivative Boards Teensy LC with bootloader Sold out
Adafruit Derivative Boards Trinket Mini Microcontroller - 3.3V
Adafruit Derivative Boards Trinket Mini Microcontroller - 5V