Gamebuino is an Arduino-based handheld console developed by Aurelien Rodot and released in 2014. According to the system's official website, which is http://gamebuino.com, these are the specs of the Gamebuino (specs of the Gamebuino might vary from model to model):
Battery - LiPo battery with up to 24 hours of battery life, charged with a regular smartphone charger
CPU - atmega328 clocked at 16Mhz
Dimensions - 90mm x 45mm x 12mm (3.5 inches x 1.8 inches x 0.5 inches)
Input - Arrow buttons and A B C buttons
Ports - 1 micro USB port, 1 micro SD card slot, 2x I2C ports
Screen - 84 x 48 resolution, black and white, auto backlight (the screens are recycled from Nokia phones)
Sound - Speaker, up to 4 channels and 8 volume levels
If you'd like to learn more the Gamebuino, interact with the Gamebuino community, download some Gamebuino software, download some Gamebuino emulators, download some Gamebuino development programs, buy a Gamebuino or get help with using a Gamebuino, including getting started and troubleshooting, I recommend you explore http://gamebuino.com, which I told you about earlier in this webpage so you'd know where I found out what the specs of the Gamebuino are.