Featured in Make: The Maker’s Guide to Boards, DFRobot Leonardo with Xbee Socket is compatible with Arduino Leonardo. The "Arduino Leonardo" is based on the ATmega32u4 chip. It is the latest addition to the Arduino family. Compared with the earlier Arduino controllers, using the ATmega32U4 as its sole microcontroller, allows the Leonardo to be cheaper and simpler to use. Also, because the 32U4 is handling the USB directly, code libraries allow the board to emulate a computer keyboard, mouse, and more using the USB-HID protocol!
image courtesy of Make Magazine
Based on the "Arduino Leonardo", this one from DFRobot equips an XBee socket and 3 sensor extension pins for your application. The Xbee is a commonly used wireless communication module with 2.4G Zigbee,900Mhz version, etc. The socket makes it possible for you to extend the XBee or XBee form factor wifi, Bluetooth, and RF modules for your Arduino directly. However, the D14~D16 extension pins with power supply maximize the use of your ATmega32u4 microcontroller. They support the digital sensors and modules from DFRobot directly.
Notice: This board is only supported in the latest Arduino IDE 1.0.1 or later version, so you must update the IDE.
Specification
Input Voltage (recommended): 7-12V
Input Voltage (limits): 6-12V
Microcontroller: ATmega32u4
Operating Voltage: 5V
Interface: Micro USB
Compatible with Arduino Uno R3 series pin mapping
Directly support Xbee and XBee form factor wifi, Bluetooth, and RF modules
Extend D14~D16 digital pins with 5v power supply
Clock Speed 16 MHz
Size: 70x55x14mm (2.76x2.17x0.55")
Microcontroller Specification
Digital I/O Pins: 20
PWM Channels: 7
Analog Input Channels: 12
DC Current per I/O Pin: 40 mA
DC Current for 3.3V Pin: 800 mA
Flash Memory 32 KB (ATmega32u4) of which 4 KB used by the bootloader