If you have been using Windows 8 for a while, you might have noticed that closing an app Windows 8.1 by dragging down will keep it in memory. But it stays in a suspended state, which means that the app will sit on the system without using any of the processor’s power and just a tiny fraction of memory (less than 1MB on well-coded apps).
All this means that apps in Windows 8.1 still work like in smartphones, they don’t need to be closed, the operating system is smart enough to keep many suspended apps (a.k.a doomed), and when your PC needs more resources to take up on a harder task, Windows will automatically close all the necessary apps by cross referring and closing the oldest first. And don’t worry when you switch back to an app, it will resume where you left off.
Although, this is a great technology, there will be times when a particular Metro-styled app may just stop responding or it’ll start acting up and you’ll need to force an app to close. In Windows 8.1 to close an app, you now have to drag it down and hold until you see a flip animation, then release (This is also applicable to Windows RT 8.1).
It’s worth noting that this way to close apps in Windows 8.1 is only working on a few apps, like Internet Explorer, Reading List, Calculator, Sound Recorder, and a few more. In other words it works on the new modern apps released for 8.1, other apps such as News, Netflix, People, etc., will close seconds after you terminate them like you used to in Windows 8.