Siri might not be as exclusive to the new Apple iPhone 4S as we were led to believe, given that it has been ported onto an iPhone 4.
According to GSM Arena, developer Steven Troughton-Smith has been working with 9to5Mac to get Siri up and running on the iPhone 4. Porting Siri onto an existing iPhone required Troughton-Smith to install Siri and Springboard files onto the iPhone 4.
The port is still in its initial stages, as seen from the sluggish performance on the iPhone 4 after the Siri port. Nonetheless, after a few hours of refinement, the user interface was back to normal. However, Siri is still not full functional on the iPhone 4, since Apple's servers only accept requests from the iPhone 4S at the moment.
If Troughton-Smith and 9to5Mac are able to get Siri working properly on the iPhone 4, the reasons for current iPhone 4 owners to upgrade to the new iPhone 4S will dwindle down to a faster dual-core A5 processor and an 8-megapixel camera made by Sony.