Required:

Siri files extracted from an iPhone 4S.
OpenSSH and iFile (found on Cydia)
SFTP client (WinSCP for Windows and CyberDuck for Mac OS X).
Jailbroken device running iOS 5 public release only

STEP 1: Extract the files attached in “Siri.zip” downloaded above.

STEP 2: Now open your SFTP client (WinSCP in this guide), write down the required info.



Host name:<type the IP address of your network from the WiFi settings on your iPhone>
Username: root
Password: alpine

STEP 3: Now open the following directory and copy AssistantServices.framework which can be found in the extracted files you have downloaded.

/System/Library/PrivateFrameworks/



STEP 4: Now head to the below directory and copy all files found in SpringBoard_Assistant_pics folder.

/System/Library/CoreServices/SpringBoard.app



STEP 5: Once done, get on your iPhone and open iFile and get to the same directory of the previous step. You’ll find a file named N90AP.plist for iPhone or N81AP.plist for iPod touch. Tap on that file, edit it and type this:

<key>assistant</key><true/>
after
<key>720p</key><true/>


STEP 6: Finally give your device a “reboot” not “respring” and you’ll get Siri GUI. Just hold down the home button and you’ll get it.



If Siri GUI didn’t appear after the above steps, then you may want to try AssistantServices.framework instead of the one in STEP 3.


*These are only the instructions for the Siri GUI. That means you will not be able to talk to Siri just yet but there has been a confirmed update that this has been done so just be patient and you'll be able to have it soon.





Here's a video of the iPhone 4 compared to the iPhone 4s running Siri




Mark Gurman interviewed the developer.

quote:

Full interview below:

Mark: Where do you go from here with the port?

Steven: At this point it’s all about confirming this works across devices, making it reproducible (we got it working on two devices today), and documenting everything. It does require files from an iPhone 4S which aren’t ours to distribute, and it also requires a validation token from the iPhone 4S that has to be pulled live from a jailbroken iPhone 4S, and it’s about a 20-step process right now.

Mark: In its current state, is the port 100% functional, is there anything you would like to see work better?

Steven: Yes, it seems to be 100% functional. I’m working on the rough edges, but everything that works on the iPhone 4S seems to work here

Mark: Do you ever see Siri showing up in Cydia (or another jailbreak store) for non natively supported devices?

Steven: No, I could not be a part of that. I have no doubts that others will package this up and distribute it quasi-illegally, or try and sell it to people. I am only interested in the technology and making it work; proving that it works and works well on the iPhone 4 and other devices

Mark: So, you also got Siri working on the fourth-generation iPod touch, how is that working out?

Steven: We got chpwn’s iPod touch up and running with Siri after proving it works on my iPhone 4. Unfortunately the microphone on the iPod is nowhere near as good as the iPhone – you will notice that the Siri level meter hardly moves when you talk to it. While it does work, you have to speak loudly and clearly to the iPod

Mark: How long did porting take you, what was the “I got it” moment?

Steven: Basically, I already had everything I needed to make it work. I had spent a lot of time mapping out in my head exactly how Siri works on the iPhone. All I needed was access to a jailbroken iPhone 4S to put my hunch to the test. It literally took no longer than 10 minutes to put all the pieces in place and perform our first test on my iPhone 4, and it was an instant success.