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Topic: Hardware

The time displayed on most Android phones is wrong

Summary: The problem dates back to an Android bug first uncovered in December 2009.

Adrian Kingsley-Hughes

By for Hardware 2.0 |

Did you know that the time displayed on most Android handsets is wrong? Dr. Neil DeGrasse Tyson explains why to Joshua Topolsky in the latest episode of On The Verge.

Tyson talks about the issue at the 15m 20s mark.

Most Android devices set the time based on the data they receive from GPS signals. While the clocks on the GPS satellites are incredibly accurate atomic clocks, the timekeeping system used by them was defined up to 1982.

A total of 15 'leap seconds' have been added to the Coordinated Universal Time (UTC) time scale since then, which Android handsets don't compensate for, so these handsets are running exactly 15 seconds too fast.

The GPS signal does include the offset difference between GPS time and UTC in the message it sends to receivers, but it seems that this information isn't being used by Android to correct for the leap seconds.

Interestingly enough, this has been listed as an Android bug since December 2009. It seems like an easy bug to fix, so I'm surprised it's been ignored for so long.

The iPhone also sets the time based on GPS data, but according to Tyson, iOS adds the 15 seconds into the equation, so Apple handsets show the correct time.

Related:

Topics: Hardware, Android, Google, Mobility

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Talkback

24 comments
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  • Um ... 15 Seconds?

    Who Cares?

    Ludo
    Ludovit
    Reply Vote

    • Not Google apparently

      Nor anyone else buried in the Android mess it appears. Remember, near enough is good enough if your main raison d'etre is advertising revenue and demographic data rather than professional software development.
      tonymcs@...
      Reply Vote

      • Umm, no

        Because Network Time Sync handles that functionality!

        Coincidentally, my iPad 3 and My HTC Rezound is actually 100% in sync so, not sure why you think this is a real issue. I guess simple issues for simple minds.
        slickjim
        Reply Vote

    • Who?

      You cared enough to read the blog and then add a post.

      Just sayin'
      use_what_works_4_U
      Reply Vote

  • Not true

    I just verified my Evo 4G against the clock on my Windows PC that is synced with the MS server. My phone is about 4-5 seconds slow. I was always under the impression that the phone gets its time info from the cell towers. Plus if the GPS is off, how would it get this signal anyway? I travel quite a bit and my phone has always found the correct time when I take it out of airplane mode while the GPS is still off. I'm calling Bollocks on this!
    puffmanxx
    Reply Vote

    • World renown astrophysicist vs @puffmanxx

      Not sure which one I'm going to vote for...
      themarty
      Reply Vote

    • They do

      Time Sync is part of most security protocols and any connected device is going to need to be reasonably accurate to make the connection work.
      slickjim
      Reply Vote

    • My Sensation...

      is about a minute slow...
      wright_is
      Reply Vote

    • GPS not affected by airplane mode

      GPS is not affected by airplane mode as airplane mode stops the phone transmitting. GPS is essentially passive. Granted phones often retrieve information from the internet to speed up getting a positional fix but this isn't neccessary and wouldn't be of any use for getting the time.
      mog0
      Reply Vote

  • I don't use GPS.

    How would my phone get time from the GPS satellites when I switch off GPS completely?
    kraterz
    Reply Vote

    • No GPS here

      I have GPS turned off as well.
      wright_is
      Reply Vote

  • The time displayed on most Android phones is wrong

    what a waste of space! Both story and writer.
    If this is the best they can manage, give them a written warning for failing to do their job to a professional standard
    redlandscv
    Reply Vote

  • What a crock and waste of space

    I literally never turn on my phone's GPS and my Win7 desktop and Android phone are within 1 second of each other.

    The article reads like fruit fan spam to me.
    cHarley1200
    Reply Vote

  • I wonder how this impacts networked games?

    Does this have any impact on multiplayer network games?
    eferron@...
    Reply Vote

    • Yes it does have an impact...

      But only of your thumbs are 15 seconds faster ;-)
      schmoeleco@...
      Reply Vote

  • 15 seconds?

    Ah shoot. I'm going to throw out my Thunderbolt and buy an iPhone instead.
    FortisMaximus
    Reply Vote

  • so iOS is better..

    So, iOS has the "correct" time... by 15 seconds...

    They can have their 15 seconds as Apple has its Alarms still not fixed, when a new year begind there are always problems with alarm clocks not going off.. just saying
    Florejaen
    Reply Vote

    • iOS has its own issues

      See, e.g., http://www.jwz.org/blog/2010/07/what-at-t-doesnt-run-ntpd/ where two adjacent iPhones differ by 26 seconds.
      sla29970
      Reply Vote

  • getting what you paid for

    Find IS-GPS-200F, the document describing GPS. See section 20.3.3.3 which describes the parameters necessary to correct from the SV time scale to the GPS system time scale as well as the requirement for the receiver to calculate the relativistic effects, and section 20.3.3.5 which describes the parameters necessary to correct the GPS system time scale to get UTC(USNO), including the need to monitor variations in the ionospheric delay. Did you pay enough for your cell phone to implement the algorithms for precise time? Is that really what a cell phone is for?
    sla29970
    Reply Vote

  • Forget the 15 seconds...

    Focus on what's really important: anybody else notice this is the "We got a bada$$ over here" guy?
    Ndiaz.fuentes
    Reply Vote
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