The Touch interface represents a single contact point on a touch-sensitive device. The contact point is commonly a finger or stylus and the device may be a touchscreen or trackpad.
The touch event interfaces support application-specific single and multi-touch interactions. However, the interfaces can be a bit tricky for programmers to use because touch events are very different from other DOM input events, such as mouse events. The application described in this guide shows how to use touch events for simple single and multi-touch interactions, the basics needed to build application-specific gestures.
The touch interfaces enable applications to create enhanced user experiences on touch enabled devices. However, the reality is the vast majority of today's web content is designed only to work with mouse input. Consequently, even if a browser supports touch, the browser must still emulate mouse events so content that assumes mouse-only input will work as is without direct modification.
Today, most Web content is designed for keyboard and mouse input. However, devices with touch screens (especially portable devices) are mainstream and Web applications can either directly process touch-based input by using Touch Events or the application can use interpreted mouse events for the application input. A disadvantage to using mouse events is that they do not support concurrent user input, whereas touch events support multiple simultaneous inputs (possibly at different locations on the touch surface), thus enhancing user experiences.
A Boolean value indicating whether or not the alt (Alternate) key is enabled when the touch event is created. If the alt key is enabled, the attribute's value is true. Otherwise, it is false.
A Boolean value indicating whether the control (Control) key is enabled when the touch event is created. If this key is enabled, the attribute's value is true. Otherwise, it is false.
A Boolean value indicating whether or not the Meta key is enabled when the touch event is created. If this key is enabled, the attribute's value is true. Otherwise, it is false.