What is your J-Score?

One of the apps that I installed on my new phone is Carat

Carat is a research project that aims to detect energy bugs—app behavior that is consuming energy unnecessarily—using data collected from a community of mobile devices. After running Carat for about a week, you will start to receive personalized recommendations for improving your battery life. We are based out of the AMP Lab in the EECS Department at UC Berkeley, collaborating with the University of Helsinki











If you are running Carat or decide to install it leave a comment with your device, OS and J-score I am interested to see how different devices stack up.

Carat for iOS

Carat for Android


9 Responses to What is your J-Score?
  1. David Goldstein
    August 22, 2012 | 1:06 pm

    Great find! In just installed this on my iPhone (iOS 5.1.1). I’ll let you know when I get a J-score.

    • David Goldstein
      August 28, 2012 | 8:31 am

      I’ve been running the app for nearly a week now but doubt it’s accuracy. My J-Score is 35 but as low as that is it’s that’s not why I doubt it. In the Actions tab it keeps telling me to close an app that is already closed. How accurate can the J-Score be when it doesn’t even recognize the difference between an open and closed app?

  2. Ray J Bilyk
    August 22, 2012 | 1:40 pm

    Looking like the links point to the other device. (Carat for iOS points to the Google Play Store, and Carat for Android points to iTunes)

    • Mitch Cohen
      August 22, 2012 | 1:51 pm

      Nothing like a little Dyslexia 🙂 they are fixed now thanks for pointing it out

  3. Chris Whisonant
    August 22, 2012 | 2:09 pm

    If I install it, it will just tell me to stop playing Kingdoms of Camelot to save on my battery! 😀

  4. Vitor Pereira
    August 24, 2012 | 4:02 am

    Interesting! I just installed on my Nexus S running Android 4.1.1, I’ll post score when I get it.

  5. Lynnete Damiano
    October 21, 2012 | 11:48 am

    My j score was 86 then I went out and used my battery a full 19 hours and the next daymy j score was 77. It said my battery life is six hours.how can this be? I have a 3800 mah extended battery that gives me about 24 hopes of use when I use my device heavily. I wrote carat to see what they had to say but haven’t heard back from them. If it’s truly monitoring our use how can it possibly at my battery lasts 6 hours when just the day before I ran it 19 straight hours workout a charge. My point here is this app is far from accurate. I’m simply perplexed that After using my battery for 19 full hours it drops my j score and says my battery lasts six . If they are going to do this project they need to be A whole lot more Accurate! That is a 13 hour discrepancy. So their data retrieval is extremely inaccurate! Hopefully they will fix this or the whole project will be inaccurately documented. I think carat is a great idea is just grossly inaccurate. Perhaps with time they can become better.

  6. Lynnete Damiano
    October 21, 2012 | 7:57 pm

    J score just updated Again to 88 which is probably more accurate ad they are getting closer to my actual battery life length. I’m using a HTC sensation with a viper Rom installed . My device is rooted and running a 3800mah mugen battery. That makes a huge difference. My stock battery score would likely be. Zero.bit with this extreme battery so far I’m a 88. I guess that’s pretty good. Compared to the others with my device. The way they score its 88% better with the extreme battery. Kinda good to know the battery really does the trick. I now get 20 hours worth heavy user where as before I for 4 hours!

  7. Claus
    November 13, 2012 | 2:04 am

    As I suspected, my J score is extremely low. Actually, its almost as low as it can be. After about one weeks use, I got my score today… 1.

    I’ve uninstalled some of the hogs and bugs and killed and restarted others. But apparently for no greater gain. Haven’t the slightest idea of what to do now. Besides keeping my device hooked up to the charger 24/7 as usual. What a bummer!