Usage Timelines is a CPU and process monitor with a graphical cpu load history as notification and a list of running apps.
A trial version is available at http://www.refined-apps.com/trials/UsageTimelinesPro-release.apk
Please note that Usage Timelines cannot show information about individual processes (other than itself) on Android N/7.0 and above. Starting with Android N/7.0, Google intentionally restricted access to /proc/<pid>/ where this information comes from. This does not affect other information, like total cpu usage, the notification timeline etc. For more details, please see https://code.google.com/p/android/issues/detail?id=205565. There is no way known to us to work around this problem without Googles cooperation. Sorry.
For questions, remarks, suggestions or feedback mail us at email@example.com
---- Features ------------
✓ Extended cpu load history as notification in the notification bar (like xload/windows task manager)
✓ The colors of the notification can be configured freely
✓ Process listing
✓ Cpu and memory usage of processes (similar to "top" or windows task manager)
✓ Processes can be terminated and uninstalled
✓ Works without rooting
✓ Very low power usage
✓ Start/stop widget
✓ Supports English and German
✓ No ads
---- Power Consumption ------------
Some remarks about power consumption and performance
Set your update intervals as high as acceptable for you. Power consumption should be fine then.
Shorter update intervals lead to higher power consumption since the values are updated more often.
You may also use it just when you experience problems and turn off the notification otherwise.
✓ Usage Timelines has been highly optimized
✓ If everything is fine, Usage Timelines should be the app in the app list that uses most cpu since all other apps should be paused by android. That's normal and expected behavior.
✓ Displaying the process list needs some additional power, especially if you are working with the app (e.g. scrolling). If the process list is not shown (e.g. while you are using another app), the process list does not use any cpu power.
✓ If the screen is off, only the values for the notification history are acquired to be able to properly update the usage history as soon as the screen is switched on again. Neither the notification history nor the process list are updated if the screen is off since you could not see the update anyway, saving cpu power and lowering power consumption.