Apple Singapore does not list Siri as one of the new features of the iPhone 4S on its website. Siri lets you use your voice to send messages, schedule meetings, place phone calls and more. You can ask Siri: "Any great burgers around here?” or “Where’s the closest ATM?” and Siri will answer. Unfortunately, it looks like users in Singapore will not be able to use Siri when they purchase the iPhone 4S. The beta version of Siri is localised for US, UK and Australia and it is available in English, French and German.
No iPhone 5 but new iPhone 4S is like iPhone 4 on steroids
Singapore to get iPhone 4S on 28 October