Thanks to the untethered Jailbreak that was released a while ago, you can now port Siri to iPhone 4 or other iOS 5 devices legally. And the ported Siri is now called Spire.

According to chpwn blog, you will need to figure out what proxy address to input before you can use Siri (or Spire). And based on the method, it does not violate copyrights.

The file is available at Cydia right now. It is about 100 Mb. If you need to read more about it, click on below link.

Click Here to chpwn Blog

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