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iOS does not have an Activity Monitor or task manager the way that desktop Macs do within OS X, but if you’d like to see what apps and processes are running in the background of an iPhone, iPad, or iPod touch, you can do so using a few different methods. For most users, simply showing the multitasking bar is sufficient, but the curious can also reveal system-level processes using alternate methods with a third party app or, for users who have jailbroken their devices, the command line.
1: The Basic iOS Task Manager
Just about every iOS user is probably aware of the task manager by now, which is accessed by double-clicking the Home button. The row of icons across the bottom show what apps are running in the background, and you can flip left or right to see more of them.
The task manager only shows apps though, and if you were hoping for something a bit more specific or technical, you’ll need to turn to another solution from a third party.
2: Use a Process App like DeviceStats
DeviceStats is a free third party app that may not be the prettiest thing in the world, but it works to show you which processes are actively running in the background of an iOS device, including daemons and background tasks.
Grab DeviceStats from the App Store
Launching DeviceStats on an iPad, iPhone, or iPod touch will show a variety of tabs and options, but what we’re interested in is the “Processes” tab, which will also have a red badge on it to indicate the total number of processes running.
Scrolling through the list should reveal some familiar names of apps that you have open, things like Camera, Calculator, Videos, Photos, Preferences, Music, etc, and there will also be many tasks shown that are background processes, system tasks, and daemons.
Nothing listed within DeviceStats is directly actionable through the app itself, meaning that even if you identify a process you can’t really do anything about it unless it’s a standard app. Standard apps can be quit as usual, or killed (forcibly quit) through direct measures. There is no way to kill or quit out of background daemons and tasks running within iOS, however.
3: Using ‘top’ or ‘ps aux’ from the Command Line – Jailbreak Only
Users who have jailbroken their iOS devices can access the command line directly, either by using an app like MobileTerminal or by connecting directly to the device through SSH.
Once connected through the command line, you can use the ‘top’ or ‘ps aux’ command to see all active processes. “top” will provide a live updated list of processes, whereas ‘ps aux’ will print a snapshot of all processes and daemons, but not update any live CPU or memory usage. Processes that have been identified by ps or top can also be killed directly through the command line, but that may have unintended consequences for the iPad, iPhone, or iPod touch, and cause it to freeze up or crash, requiring a device reboot. Again, this is only accessible through jailbroken devices, which makes this option fairly limited.
