Siri was developed by SRI International, basically as the commercialization of the CALO project [0]. It was initially developed as an app, and was even available in the store. The project was then spun-off into a company, and the developers were working on versions for other platforms. Apple then bought the company, making it exclusively an iOS product and integrating it into the OS.<p>The voice recognition technology was indeed based on Nuance technology [1]. Nuance was also a spin-off from SRI.<p>EDIT: This was all after ScanSoft purchased Nuance, which means it had both Nuance and Dragon technology at the time. However, due to Nuance&#x27;s history with SRI, I would lean towards that being the more likely option, if they hadn&#x27;t been integrated by that point.<p>(I worked at SRI during the Siri spin-off time period, and worked with one of the Siri developers on another project.)<p>[0] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;CALO" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;CALO</a><p>[1] <a href="http:&#x2F;&#x2F;techpinions.com&#x2F;nuance-exec-on-iphone-4s-siri-and-the-future-of-speech&#x2F;3307" rel="nofollow">http:&#x2F;&#x2F;techpinions.com&#x2F;nuance-exec-on-iphone-4s-siri-and-the...</a>