Speech Interpretation and Recognition Interface (SIRI) is an intelligent digital speech assistant and knowledge navigator. As an application program, SIRI runs on Apple's iOS, macOS and watchOS operating systems.
The application program is based on a Natural User Interface( NUI) that answers questions, makes recommendations and delegates requests to various web services. In the early stages, SIRI only supported iPhones, later adding iPads and smartwatches.
Over time, SIRI adapts to the user's individual preferences and can personalize results. These can be results from location-based services( LBS) or assistance with route planning, hints from the appointment calendar, the personaldigital assistant( PDA), search functions on search engines, or access to the iPhone 's voice technology through the Apple Watch.