Locking the speed of the cpu on an android phone The battery life of my cell phone lasts for about 6 hours. About 2 days ago I downloaded the app CPUControl to reduce the speed of my CPU. This resulted in more than 20 hours of battery life. However I changed the settings and I haven't been able to achieve the results I had before. I have a 4 X ARM Cortex-A7 CPU with a top speed of 1.3 GHz.

When I change the speed to 600 MHz, the change only lasts about 2 minutes ant then the processor goes up to 1 GHz draining my battery life very quickly.

You can't tell the difference between the processor running at 600 MHz or 1.3 GHz, either way it's fast enough.

What happened, how come I cant lock the processor speed anymore?
I am not aware of CPUControl's settings but you can try some other applications to lock the speed. You can try KernelAduiter to perform this and many more operations.

You can change the CPU speed by specifying the minimum and the maximum and for best battery and if you're unable to do so, change the CPU governors.


If the CPU speed increases to 1.3GHz only for a few seconds randomly, set the governor to Conservative
If the CPU stays for long at 1.3GHz, check out which application is using the CPU so much.


2a. Open Terminal Emulator 


Gain root access using su
Run top and let it display results on the screen
Press Volume Down + c to terminate the command
Scroll to the top and check out the process/app using the maximum CPU. If you find that process/app useless, terminate it