The oft-ridiculed Siri voice assistant is improved in iOS 7, with a more natural-sounding voice and speedier responses to your questions. It also returns calls, plays voicemail, posts to Facebook and performs other menial tasks. Siri is now easier to train as well, a potential boon to business travelers with numerous international contacts. Say, for instance, Siri mispronounces the name "Suphatra." You can correct it by saying, "That's not how you pronounce 'Suphatra.'" Siri will immediately ask for a better pronunciation and use your spoken suggestion to create three pronunciation alternatives. You choose the best one.