I have installed a software named "Battery". Often it happens that I receive a notification from that app saying my discharge speed is 26 percent/hour and soon my cellphone will get completely discharged(within 3-4 hours). The only solution that I have found for that is restarting my phone after which my discharge speed reduces back to 3 percent/hour, 2 percent/hour. This increased my curiosity to get such an app with the help of which I may know the ram/memory consumption by each app.You don't need to worry about your RAM Consumption. WP is highly optimised so that each app is tombstoned in background in order to maintain the flow. I am a commerce graduate so i don't know about the engineering apps. Maybe someone else can tell you.