The multitasking feature allows several apps running at the same time. If you forget to close a program completely, the applications continues to run in the background, drain battery power and slow down the device. Here's how to view currently running applications in Nexus 7 tablet.
* From the Home screen open up the Settings and tap on Apps option.
* Select "RUNNING" tab at the top. It will show a list of applicsations. You can choose any unused app to close.