Complete Siri experience only possible on the iPhone 4S because of a tweaked proximity sensor

Complete Siri experience only possible on the iPhone 4S because of a tweaked proximity sensor
When the rumors about Apple's integrated voice recognition solution Siri started, it was widely believed that it will only be fully functional on the iPhone 4S, because of the faster multithreading dual-core A5 chip. It turns out that's not the exact or only reason.

Siri has been already ported with various success rates to the iPhone 4, iPad 2, iPod touch and even the lowly iPhone 3GS, proving that the software is not chained to the A5 only.

There is one small tweak in the building of the iPhone 4S, though, that might be the culprit why Siri would only work the way it is supposed to on Apple's latest handset. It is... hold on... the proximity sensor. iFixit, when taking the phone apart, noticed that little infrared sensor box was different that what we had before.

That in itself is not the reason for Siri's performance, but a software change is seemingly forcing it to always light up when the screen is turned on, instead of only when a call is coming, as in other handsets.

The sensor is used to measure the distance to your face when the screen is on, and thus determine whether to get Siri ready and waiting for your every word, says iFixit: "The 4S, however, has a neurotic tendency of always wondering how close your face is. As long as the screen is activated, that IR sensor will be shining brightly".

Here is a video from iFixit below, explaining the iPhone 4S proximity sensor deal with Siri.

source: iFixit via 9to5Mac

Related phones

iPhone 4s
  • Display 3.5" 640 x 960 pixels
  • Camera 8 MP / 0.3 MP VGA front
  • Processor Apple A5, Dual-core, 800 MHz
  • Storage 64 GB



1. vantenkiest

Posts: 316; Member since: Apr 20, 2011

she is geekishly cute :D

2. roscuthiii

Posts: 2383; Member since: Jul 18, 2010

Wait, proximity sensor? What about using Siri hands-free when driving, or do you actually have to hold the phone to your face? I didn't get to play the video... did the cute geeky girl answer that?

3. vantenkiest

Posts: 316; Member since: Apr 20, 2011

nope.. however the accelerometer and gyroscope may help with that.. or maybe the gps feature. there are ways to measure the velocity of the device so it could know that its in a car and shouldnt be at your face.

4. goflet

Posts: 50; Member since: Oct 31, 2011

talking to your phone in the public..seems kind of wacko..

5. kainy

Posts: 165; Member since: Aug 10, 2011

Nope ... if Apple says it's cool ... it's cool. Just like the FFCams ... (dull) had them for years ... now are cool. Why? - Apple ...

6. Gemmol

Posts: 793; Member since: Nov 09, 2011

you got a point once apple make it mainstream it does not make you look crazy no more, lets hope they continue doing that and android copy, so everyone who do not have apple can look crazy too no one would be left out, just like nintendo did with motion controllers

7. biophone

Posts: 1994; Member since: Jun 15, 2011

This is bs.

12. BlowJobs

Posts: 25; Member since: Jun 30, 2011

I agree, this is complete BS. That Siri would not work on previous models is just one more lie from Apple.

8. Zippo310

Posts: 4; Member since: Oct 18, 2011

The only reason that siri \"cannot\" be ported to other iOS devices is because there isn\'t enough differentiation between the 4S and the 4. As soon as the iPhone 5 comes out, I guarantee Apple adds siri to all models.

9. jamrockjones

Posts: 345; Member since: Oct 26, 2011

No kidding. They need another reason for why people should buy the new 4S over the 4, cause they definitely aren't buying them for the new look :)

10. remixfa

Posts: 14605; Member since: Dec 19, 2008

iSee you!! :)

11. Penny

Posts: 1847; Member since: Feb 04, 2011

Hmm, I think of another reason why Apple would tweak their proximity sensor to be always on: more data. Why do usability tests with test subjects when you can use the general, unsuspecting populous? Care to know the average distance from the face a person normally holds the phone for different actions?

14. choupino

Posts: 69; Member since: May 28, 2011

PENNY I agree with you 100%!!! Siri was released in the beginning of 2010 to the App Store. Apple purchased the company that developed Siri and allowed it's own iPhone customers to be used as Guinea Pigs for when they decided to use it as a revolutionary new feature on the 4S. That seems rather dirty... Don't you think??? It's like the Old School drug dealer analogy... "Here Buddy... Try this stuff... It's free and it'll make you cool Bro!!!... Nah don't worry about it, the first one's free"... Once customers got hooked and Apple was done with their year and a half of free unpaid market research, they pulled Siri from the App store and millions of customers already using it.

13. theBankRobber

Posts: 682; Member since: Sep 22, 2011

So there IS fragmintation with iphones. Lets not forget the games they develope for the dual gpu in the iphone 4s, and then say because the iphone 4 or older has no dual gpu they can't make the same quality games for them. Ironic ain't it?

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