Google hangout application for iPhone is not up to the mark yet. There many issues which users are facing on their iPhones, users have reported that they do not get the notifications instantly and moreover the application takes lot of time to refresh and show the new chat entries. Now there is also an issues that you cannot see who is online and who is offline.
Now hangout is the messenger part of your social networking profile named as Google Plus, if you have multiple friends who have initiated a hangout on their account and keep troubling you again and again then you will definitely want to get rid of the notifications of those hangouts by just muting them. Go through the steps mentioned below and you will be able to mute the notifications of any chat or hangout on your applications so that it will not trouble you again.
Open the application and then tap the hangout or chat which is supposed to be muted.
Now tap the icon as highlighted in the screenshot.
Now you can turn off the notification and like other Instant Messaging applications it will not Turn On back after specific period of time. You will have to manually turn it ON.
So with the help of this you can get rid of the vague notifications which your group has been putting off on your iPhone. Follow these steps and then let us know if this troubles you.