Auto Memory Cleaner is usually left running in background, automatically doing all the work for you. You can set it so if you want to clean up memory at a specific time or every time when the screen is turned on/off. Auto Memory Cleaner also lets you restart any running process manually.
Some of the app’s features are reserved for the premium version, though. Auto memory cleaning when screen goes on and in specific daytime are available as in-app purchases. But the rest of the goods, such as auto mem cleaning when screen goes off and mem cleaning for specific apps, listing of the running processes, memory graph & infos, are up for grabs. Customization runs reasonably deep — for example, you can exclude certain apps from the memory cleaning routines.
A solid app overall, Auto Memory Cleaner can be downloaded from Google Play.