SAN JOSE, June 10 -- The problem Logitech is trying to solve with its new Mobi Fold mouse is not a technical one. It is a behavioral one. The company's own research found that while nearly three-quarters of professionals own a mouse, only about one in four actually bring one when working outside the office. The Mobi Fold, which went on sale Wednesday for $80, is Logitech's answer to that gap - a device designed to collapse small enough that leaving it behind feels like a deliberate choice rather than a practical necessity.

The mouse folds in half like a clamshell phone, collapsing to a 2.2-by-2.5-inch rectangle less than an inch thick and barely over two ounces. Unfolded, the two halves lock into an arched position that keeps the click b...