The mini dock provides power to the Omega2, and it allows you to plug in USB devices. It is designed primarily for volume-constrained applications, as well as applications that do not require any Expansions (networking, for example). The Mini Dock functions very similarly to the Expansion Dock. It supplies your Omega with power and allows you to communicate serially via a Micro-USB port. It also has a USB type A connector for you to use. All of this with a fraction of the size of an Expansion Dock.
The mini dock is tiny. It is approximately 4.3cm (1.7in) long, and 2.7cm (1.07in) wide. It's the same size as the Omega. It does not have the Expansion Header of some of the other Docks, but this makes it perfect for Omega-only or USB-based projects.
The mini dock is powered by the Micro-USB port that supplies 5V to the Dock. This voltage is stepped down to the required 3.3V required to power the Omega, and also provides 5V to the USB Host port. The dock allows for easy communication via the USB-to-Serial chip located in the center of the board.
The reset button, located next to the USB Connector, can be used to quickly reboot your Omega, or you can hold it down for a factory reset if your Omega is ever in a bad state.