A small application developed because HTC’s Twitter client, Peep, does not automatically shorten URLs. ShortenMobile is a small background program that watches the clipboard of the device and automatically shortens the URLs for you, currently only working with bit.ly.

Download and install the CAB to your Device and open ShortenMobile from Start Menu. If you want the app to automatically run at startup, activate the checkbox “Run at startup”. Tap the Hide-Softkey which will take the application to the background, copy any internet address (including “http://” at the beginning) to the clipboard and the automatically shortened URL will be available in the clipboard after the confirmation dialog has been shown.

(Source: XDA Developers)