Its no doubt that Siri is the biggest selling point for the Apple iPhone 4S, so it shouldn't come as too much of a shock that Apple has confirmed that it will stay exclusive to their flagship smartphone.This news will come as a disappointment to some as reports pointed to a possible official port of Siri to the iPhone 4.
Unofficially developers have managed to hack Siri to work on the Apple iPhone 4 (GUIDE) and the Apple iPhone 3GS (DEMO) which is proof of concept that the older iOS devices are more than capable to run Apple's digital assistant. The company however is sticking to hold onto the feature as a trump card as the iPhone 4S doesn't offer much of an upgrade to some over the iPhone 4 by retaining it's physical appearance.
Apple shared this news in response to an email by Michael Steeber, who suggested that Apple could consider selling the Siri voice assistant as an add-on for older iOS devices