16GB. Includes aftermarket USB to 30-pin dock connector (wore out the original one). Headphones not included (wore those out also), but it has a standard headphone jack. Includes Nike+ fitness app as well as support for audio & podcasts as well as pictures. When headphones are connected, it opens FM tuner functionality to listen to the radio. when headphones with a built-in microphone are connected, voice memo functionality is enabled. The battery had support for 24 hours of playback brand-new, but the battery has lost some of that due to age. The device has been fully restored to factory settings.