The reason why is that the 3 series of iPhone were not equipped with retina display, so restoring CoPilot Live on a new iPhone 4S may cause this reduction in mapping size. But we’ve a solution.
First, quit the CoPilot Live application. Then in iPhone SETTINGS, click on the CoPilot Live App. At the top of the screen, switch to RESTORE DEFAULTS. CoPilot Live should then be restored to its original screen sizing.

