Push notification component makes you to alert for Messages and Calls from your contacts.
If you are an other tab/chat and you received a message from the user then the notification will alert you have an incoming message. If you click the incoming message then it will redirect to respective user.
If you are other tab and you received a call from the user then the notification will alert you have an incoming call. If you click the incoming notification then it will redirect to caller screen.
If you missed incoming call then you have missed call alert. If you click the missed notification the it will redirect to calllogs page.