“There are two components: an application for your BlackBerry, and one that can be used on an unlimited number of PCs. To initiate Internet access, you launch the program on your desktop. If the BlackBerry is not connected via USB the program will prompt you; after the device is connected it will prompt you to start the TetherBerry app on the device. When running, the app displays status information (as shown at right).If you wander in and out of signal coverage, the app will not re-initiate itself but will display an error message instead.” Read more here: