The amount of instruments at your disposal is huge. You can find various types of guitars, banjos, drums, pianos and keyboards, and even a techno rhythm box.
All the instruments can be played in a simple version just by using the mouse, and without requiring a great deal of effort or sense of rhythm. There is also a pro version, which is played with the keyboard and requires a little more musical knowledge.
JAM is a somewhat experimental application that music aficionados are certain to enjoy. The app also comes with an option to share a link on the social networks, such as Twitter and Google plus, and invite your friends to join the fun.