watchOS supports modal interactions through modal sheets, alerts, and action sheets. When any of these modal views appears, it takes over the entire screen, covering the previous view until people complete the modal task or dismiss the interaction.
In the streamlined, glanceable environment of Apple Watch, modal interactions are great for delivering timely, critical information and helping people make simple, straightforward choices. Here are several ways a modal interface can enhance the user experience.
Bring attention to key information. For example, when the system can't locate a device on which to play audio, it uses an action sheet to let people choose from a list of recently used devices.
Streamline interactions. For example, Music makes it easy for people to rate items in their music library by listing three mutually exclusive options in a nonscrolling modal view.
Confirm intent (expected for destructive actions). For example, when people initiate the deletion of a song, Music displays an alert that lets them confirm their intent to delete the song or cancel the action.
Present purchase options. For example, a subscriptions app can help people compare options and make choices by using a modal view to present all the actions and information required in a purchase flow. (Note that the partial subscription screen above shows only a subset of required elements; for guidance, see Making Signup Effortless.)