iPhone 4 can run Siri, as seen in Jailbreak Hack
You could debate whether the “killer feature” of the new iPhone 4S is the 8 megapixel camera, the A5 processor, or the Siri personal assistant, but one thing is for sure—those of us still using an iPhone 4 would sure love to be able to talk to our devices. Luckily, it looks like that will be possible for those with jailbroken devices thanks to Steven Troughton-Smith.
As seen in the video below, just days after the release of the iPhone 4S, the developer has managed to work some magic and bring the Siri software to the now-outdated iPhone 4. It was pretty easy to see this coming, but maybe not so quickly, and definitely not working as smoothly as it appears to be.
… This puts potential 4S buyers in an interesting position. If Siri is seen as a main attraction, then one would have to at least consider just jailbreaking and making do. Of course, the new phone comes with several other noteworthy features, it’s just that they’re hidden on the inside, which is less satisfying for those who like to appear on the cutting edge. With Siri running on the iPhone 4, swallowing the price of upgrading to a 4S may become much harder for a select group.