Call waiting is a feature which reminds you that an incoming call is coming while you were engaged with another caller on your mobile device. Android has included a feature in your device which enable your device to vibrate when another caller calls you on the device while you are busy in conversation with any other caller. At this juncture, you may decide to end up your current call and may start conversation with the new caller or you may decide to continue the current conversation.
It is easy to activate vibrate on call waiting feature but if you feel any problem, you may see the instructions.
1: Tap the icon of the ‘Dialer’ app at the bottom left corner of Home screen of your Android 6.0.x Marshmallow smartphone and device to open up the ‘Dialer’ app screen.2: Tap the 3-digit settings button at the top right corner of the ‘Dialer’ app screen but immediately below the status bar. It will open up a popup menu.3: At the popup menu, tap the ‘Settings’.4: At the ‘Settings’ screen, tap the ‘Sounds and vibration’.5: At the ‘Sounds and vibration’ screen, see the ‘Vibrate on call waiting’ is not checked, i.e. not enabled and activated.6: If you want to activate the ‘Vibrate on call waiting’, tap this feature to activate.That’s all!