UI Shield:

• MicroSD card slot.
  
• USB gamepad support (Uno model only).
  
• Atmega328p coprocessor to handle SD card and USB access.
  
• 32 KB of extra RAM.
• Pin-compatible with Gameduino and Gameduino 2.

GFX Shield:

• 15-pin VGA output with 320x240 resolution.
  
• 18-bit color depth.
  
• 512 KB of image data.
• 4 palettes of 256 colors each.
  
• 4 tiled background layers.
  
• 256 sprites.
  
• 3.5mm stereo audio output.