Siri is a built-in “intelligent assistant” that enables users of Apple iPhone 4S and later and newer iPad and iPod Touch devices to speak natural language voice commands in order to operate the mobile device and its apps. Users can speak commands — and receive audible confirmation from Siri — to send messages, place calls, set reminders, operate iTunes and more.
Siri can work across multiple iPhone and iPad apps as needed in order to accomplish its tasks. Siri also supports extended dictation, enabling users to have their words translated into text for use in e-mail and text messages, Facebook status updates, tweets, note-taking Web searching and similar operations.
Siri also features prominently in the Siri Eyes Free and CarPlay technologies from Apple that provide voice command support of a car’s audio system or in-vehicle infotainment system.
Siri was added to MacOS starting with MacOS Sierra.
iOS 11 included a number of Siri advancements, such as new voices and personalities, a deep learning-based text-to-speech voice, the ability to handle follow-up questions and language translation, and a personalized recommendation engine.