Oh, and Piriform – just because something is 'most requested,' doesn't mean that it's good. So yeah, it was a short run for CCleaner, but at this point it's probably best to stay far, far away. Just know that Android is capable of handling the memory it has to work with, unlike Windows or other operating systems that tend to get janky once the used memory hits a certain critical point. I'm not going to go into all the details about why task killers on Android are basically Hitler, but here is a good write up that covers the basics for anyone who may be interested in learning more.