Later devices used capacitive sensing which does not require a stylus. The touch sensitive lower screen accepts input from the included stylus. In Reader navigation works with a keyboard, mouse, stylus, or through electronic bookmarks. The board and app communicate using a Bluetooth stylus. Interaction can be by finger or a capacitive stylus, available for separate purchase. Display resolution was announced to be , paired with a stylus pen. It is designed for use with a stylus and a graphics tablet or tablet computer. The IBM Simon had a stylus, used to tap the touch screen. The ink-wet brush creates a line quite different from a sharp stylus. The device cannot tell the difference between a finger and a passive stylus. There is no electronic communication between a passive stylus and a device. Mouse gestures use this principle by using mouse movements instead of a stylus. It is the only stylus currently supported on iPad Pro models. Menu selections were made with a stylus rather than a mouse. Writing was accomplished by scratching the wax surface with a stylus.