Siri (
Speech
Interpretation and
Recognition
Interface) is a part of
Apple Inc.'s
iOS,
watchOS, and
tvOS operating systems. Siri is a computer program that works as an
intelligent personal assistant and
knowledge navigator. The feature uses a
natural language user interface to answer questions, make recommendations, and perform actions by delegating requests to a set of
Web services. The software, both in its original version and as an iOS feature, adapts to the user's individual language usage and individual searches (preferences) with continuing use, and returns results that are individualized. Siri was originally introduced as an iOS application available in the
App Store by
Siri Inc., which was acquired by Apple on April 28, 2010. Siri, Inc. had announced that their software would be available for
BlackBerry and for phones running
Android, but all development efforts for non-Apple platforms were cancelled after the acquisition by Apple.