New voices for Siri and peer-to-peer payments are among the new features in the next version of Apple's mobile device operating system iOS 11, previewed at the company's annual Worldwide Development Conference on Monday. "With the new operating system, Apple has doubled down on many of the applications it has developed for iOS," said Ross Rubin, the principal analyst at Reticle Research. "Much of the enhancement of the OS has come via those core applications versus general new functionality," he said.