Siri
Siri was originally released as a stand-alone application for the iOS operating system in February 2010, and at the time, the developers were also intending to release Siri for Android and BlackBerry devices. Two months later, Apple acquired Siri. On October 4, 2011, Apple introduced the iPhone 4S with a beta version of Siri. After the announcement, Apple removed the existing standalone Siri app from App Store. "TechCrunch" wrote that, despite the Siri app's support for iPhone 4, its removal from App Store might also have had a financial aspect for the company, in providing an incentive for customers to upgrade devices. Third-party developer Steven Troughton-Smith, however, managed to port Siri to iPhone 4, though without being able to communicate with Apple's servers. A few days later, Troughton-Smith, working with an anonymous person nicknamed "Chpwn", managed to fully hack Siri, enabling its full functionalities on iPhone 4 and iPod Touch devices. Additionally, developers were also able to successfully create and distribute legal ports of Siri to any device capable of running iOS 5, though a proxy server was required for Apple server interaction.
Over the years, Apple has expanded the line of officially supported products, including newer iPhone models, as well as iPad support in June 2012, iPod Touch support in September 2012, Apple TV support, and the stand-alone Siri Remote, in September 2015, Mac and AirPods support in September 2016, and HomePod support in February 2018.
MessagePad
The MessagePad is the first series of personal digital assistant devices developed by Apple Computer for the Newton platform in 1993. Some electronic engineering and the manufacture of Apple's MessagePad devices was undertaken in Japan by the Sharp Corporation. The devices were based on the ARM 610 RISC processor and all featured handwriting recognition software and were developed and marketed by Apple. The devices ran the Newton OS.