Double Launcher 2.16

the author of this app says:

This program lets you to launch up to four different applications from each Pocket PC hardware launch button, including the record button. You can configure each button to work by setting it to be pressed, pressed and held, double-pressed, or double-pressed and held.

You can also assign functions to the buttons including record, launch Today screen, pop the input panel up and down, simulate various keystrokes, open documents, rotate the screen or power the device down, and more.