Iduino_Yun_Shield, an extremely powerful development for Arduino board, is designed to solve the problems of connection and storage which exist in the Arduino board. Iduino_Yun_Shield runs Open Source OpenWrt System (Same system as runs in Arduino Yun) and it is fully compatible with Arduino IDE V1.5.4 or later versions. Yun Shield is an ideal choice for Arduino Projects which require various internet connections and more storage.
Actually, Iduino_Yun_Shield is equal to the official Arduino Yun, but Iduino_Yun_Shield is more flexible because it can work with other Arduino board such as Uno, Duemilanove, and Mega etc. Iduino_Yun_Shield uses external antenna which provides stable connection under various environments.
If you want more detail about Iduino_Yun_Shield, please visit our wiki
If you want to buy it, click here