I worked on a recent forum post concerning the "swipe-down-to-kill" behavior in Windows Store applications, and want to fully explain what's going on with a small but important change between Windows 8 and Windows 8.1.
In Windows 8, we introduced Windows Store apps – and one of the great things about a Store app is that its life cycle is managed by Windows 8 for the user. When a Store app is not on screen, it goes into a Suspend mode, which reduces the app’s usage of the CPU and disk i/o – if the system ever needs the memory being used by the suspended app, the app will be terminated to free up the memory. You don’t have to worry about suspending and terminating apps – Windows takes care of that for you!
Even though user termination of Store apps was not necessary in Win8, it was still achievable via a classic means: Alt-F4. Additionally, a new touch-friendly Close gesture was invented for termination: swipe from the edge of the app (across the screen bezel) down to the bottom of the screen. The app would shrink and disappear as you swiped off screen, and terminate – similar to Alt-F4 or the Task Manager.
A result of the Close gesture behavior in Windows 8 is that whenever an app was terminated, it could take a long time to reload the next time you switch to it (especially on lower-end machines and certain architectures) because the app needs to go through a full restart. In most cases, the user simply wants to remove an app from visibility when the user is done with it – and by terminating the app, the user inadvertently incurs a performance penalty the next time the app is launched.
In Windows 8.1, we made a subtle change to the Close gesture to address this issue: instead of terminating an app, the Close gesture now only suspends an app. This allows the user to easily remove an app from view without terminating it, and also instantly resume the app from suspension to its previous state the next time it's needed – no need to wait for a full app reload!
Additionally, we’ve built in a few extra features to give users a bit more power.
Sometimes your app is buggy, and you simply want to restart it to a fresh state. If you perform the Close gesture on an app, and then immediately relaunch the app (from Start, Search… etc.), the app will terminate and restart as a fresh instance. This allows users to easily restart an app that is misbehaving. For example, if an app hangs on
a particular page, you can do the Close gesture and immediately launch it again to get a fresh instance of the app.
Lastly, if you really need to terminate your app, you can do the same Close gesture but hold the app at the bottom of the screen for a moment and wait for it to “flip” around, then continue swiping it off the screen. This will terminate the app and can be used if you don’t want to resume your app later. However, as we mentioned earlier, for most users the swipe Close gesture that suspends apps should be sufficient – let Windows take care of the rest for you!
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