If you double-click the “Home” button on the lower center of the iPad’s (or iPhone’s) screen, a “task bar”-style display will open on the bottom of the screen, with icons for all of your recently used apps. Some of these apps may be running in the background, others are “frozen,” meaning they are not active or running in the background. Still others are simply shown as recently active apps.
Regardless of their status, the apps shown in this display are consuming RAM and may be affecting your iPad’s performance.
It is good practice to clear this display, especially if your iPad begins to feel sluggish. Tap and hold your finger on one of the app icons until all the icons begin to “shake” and a red circle with a minus sign appears. Now you can tap on an icon’s circle/minus sign to completely turn off the app and to remove it from memory.
When you are finished shutting down the apps you want, either press the Home button again or tap elsewhere on the iPad screen to return to the home screen and normal operation.
Note that fully shutting down an app and removing it from the “recent” apps list does not delete it from your iPad. It simply turns off the app and restores the RAM it was using.