I use 3 specific tools to combat this. Greenify lets you put apps into hibernation so they don't use your CPU:
https://play.google.com/store/apps/details?id=com.oasisfeng.greenify&hl=en
Battery Doctor is great for killing background processes:
https://play.google.com/store/apps/details?id=com.ijinshan.kbatterydoctor_en&hl=en
And Clean Master gets rid of all the file system cruff that builds up:
https://play.google.com/store/apps/details?id=com.cleanmaster.mguard&hl=en
All three of these have options to automatically clean/hibernate. Greenify can create a shortcut for you to manually put apps to sleep. I'd take a few minutes to play with them and see how they work for you. They are all available for free. :)
This combination has worked for me with several phones, I hope it does for you as well....