– Force close any app: If an app is not working properly or freezes, and you don’t seem to be able to do anything then try this trick. This is for those times when no key or touch helps you close the app. Force close the troubling app from Settings menu. Go to Settings > open Apps sub menu and choose from the list the app that is being dead. Tap on the Force Close to shut down the app completely. 

You can also see all the running apps in the right side of the screen. Tap on Stop to have the easy way of force closing any app on Android.

– Restart your Android device: another simplest way to unfreeze Android smartphone – or any other OS, for that matter – is to simply restart the device. Press the Sleep / Power button for a few seconds and push it to Restart. However, this Android tip will only work for those times when your device is still responding to you.