The main uses of magnetic door screens, according to bugoffscreen.com, are to keep bugs out of the house, to have an easy pet door, and to accommodate high-traffic events where guests frequently go through an exterior door. Typically, they are easier to install than regular screen doors.
A magnetic screen door allows a doorway to have a temporary screen for less than the cost of a permanent screen door. Entry and exit through a magnetic screen door is hands-free and available for almost any size doorway, claims bugoffscreen.com. Magnetic screen doors generally are easily removable and reusable, and they provide a convenient way to have a screen door without the cost and installation difficulty.