Default An App to see what apps cause high CPU usage?

I know about cpuspy, better battery stats and apps like it. They allow you to see how long your cpu has been running at different speeds. My question is there any app that tells you exactly what App/process cause the cpu to go to a particular(highest speed). Getting really good battery life on the LG G2 and think I can make it better by using Per App Modes to tune down the CPU speed in apps that use the most power.