The App Can Tell You What’s Draining Your iPhone’s Battery


A handy find by folks at Cult of Mac that can give you a good idea of all that is running on your iPhone in the background  is an app called Activity Monitor Touch which is basically a tiny port of the Mac version. The app displays tables and graphs for your device’s performance stats such as processor, memory usage, battery level and uptime as well as a list of running processes. You can even setup an alert by tapping the alarm icon besides the battery which goes off the moment your battery is fully charged.

Testing the app, the source notes:

One fun trick is to quit some background apps while viewing the memory usage page – you’ll see the used memory bar shrinking down as you tap wiggling app icons in the running-apps tray at the bottom of the screen. (To get to it, double-tap your device’s home button, then tap-and-hold on any of the icons you see.)

Unlike the desktop app, this doesn’t let you meddle with running apps directly. You can’t quit processes from the list of what’s running.

Here’s the official iTunes desctiotion:

? Just like Activity Monitor on your Mac, AMT is the most handy and pretty system monitor app in the App Store!
? 4 in 1 app: Battery Status, Usage Monitoring, Device Information, and Process Monitoring
? Increase battery life by ensuring full-charge with sound alert
? Beautiful, useful, and universal. Buy it once and use it on your iPhone, iPod Touch, and iPad!


– Supported models: iPhone original / 3G / 3Gs / 4, iPod Touch 1 / 2 / 3 / 4, iPad WiFi / 3G, iPad 2
– Overview page showing device UDID, capacity, free memory, battery power, and network state.
– Detailed usage information on memory. View free space and realtime CPU activity.
– Battery state and remaining time for standby, gaming, surfing the net over WIFI / 3G, audio / video playback, and reading books.
– Alert message & sound when battery is fully charged.
– Active process list.

You can download the free version of the app from here which only shows device overview and battery info or grab the full version for $2 from here.


  • Anonymous

    Nice misleading title.

  • Frank Williams

    How can you tell which processes are using battery more than other?

  • Ari

    Probably by looking at what happens to the CPU usage when you quit an app and seeing if it goes down.

  • Jbohn

    TYPO: desctiotionAnd formatting issues for the bullet points (multiple question marks)

  • Jbohn

    and formatting issues for my post as well!

  • Jbohn

    And both links go to the Free version.

  • Anonymous

    There are other things that drain battery besides the CPU.

    On the 3GS I was using until last week, once the battery dropped below 20%, firing up any app that used GPS (Maps, Camera, etc) or 3G wireless would cause an sudden, uncontrolled shutdown (screen would just black out and I’d have to reboot the iPhone). The front and back surfaces would be warm, too, suggesting the GPS and 3G antennas were drawing far more juice than the 2-year-old battery could provide after falling below 20%.

    I could successfully reboot the 3GS once after that (if I used 3G or GPS again, it would die again and during the second reboot it would say it needs charging), and there’s surely lots of CPU usage while loading the OS into memory.

  • You’re right, this article is a total disaster.

    I don’t think seeing which apps are running and how much memory they are using is all that helpful. 

    I was able to diagnose a couple problems using an app called ‘AppSwitch’, because it has a console feature that lets you see system and crash reports. I noticed in the console that my phone was constantly using location services to get my time zone. So I turned off that feature, and it greatly improved my battery life. This bug seems to be fixed in 5.0.1.

    You can also use the Console feature in ‘AppSwitch” to see if any of the iCloud services are crashing. Sometimes a corrupted contact or bookmark can cause your phone to be constantly syncing.