[Nexus 6 Q&A, Help & Troubleshooting] ElwOOd_CbGp:
yea there's two built-in ways to view running processes. One is directly Settings. Scroll down to where it says Memory. Open and check it out. I know. Google might as well not even wasted their time making that activity since it's next to useless. The other one is located in Developer Options. It's labeled "Running Services" and gives you stats on what apps are running, how long, etc. Yea, not very helpful either since there isn't much you can do besides uninstall some things or do the root and ransack thing. It's intentionally made like that, just like the way android battery stats are completely useless for nailing down offensive background services. Google likes it that way. They make money by tracking your location and serving you up with as many ads as possible. While it's true what dude said about the way Android preloads and makes a lot of stuff ready in RAM, hibernating, and using task killers is basically like working against your system resources, don't listen to people who yell things at you because they've been brainwashed by companies and developers who want their services installed, front-and-center, autostarting, and running 24/7 in your device's memory. Why else you think every website has a banner talkin' bout "oooh ooh install our app" and grant as many permissions as possible while some even go as far as sabotaging their own services via their website so users feel forced to install the app. They don't care about you, your cpu, or your experience as long as it's filled with ads and periodically uploading analytics and usage stats and the best way to do that is to have background and persistent services to silently restart their location polling or pointless notification systems designed solely around getting you to interact with the app. I'm not talking about things like email, messaging, or whatever other app you depend on or feel is important enough to keep close at a tap of finger. My suggestion is to analyze those settings activities I named earlier or a 3rd party one like BBS and make some decisions about what you are willing to delete. Compromises can be made depending on what's important to you and also with root. Half (or more) of the apps in your phone that have boot receivers and other various event listeners up the wazoo have no business knowing your phone is even on until you tap it's little icon. This is opinion of course because others will tell you you're breaking android and a bunch of other nonsense they've been fed by google to address the people, like me, who are tired of seeing google and other apps (usually ones my by behemoth corporations) that run constantly in the background even though I open up and use whatever particular app maybe once a week. If you're rooted, there is a lot you can do to take control of apps that like to stay nudged up as close as possible in the queue and keep open connections. It all depends on you and how you use your device. Don't listen to know-it-alls who yell at you IN ALL CAPS. Either accept the fact that google, facebook, admob (and whoever else app you have that thinks it's the most important) own your phone, or do a little research for yourself because regardless of what homeboy said, it's easy to see that available RAM feels way smoother than ram that has to wait for android to move pokey balls out of the way...just sayin