I have an iPhone 4 with the Google Voice messenger app. However I don't get notifications at all; I've tried everything! If I want to check if I recieved a text I have to go into the app and press the refresh button. Any suggestions?
It would be probably a bug with the app. Can you check that you have notifications on for this app, by going into the following setting:
Home Screen > Settings > Notifications > GV Messenger.
Additionally the GV Messenger is not the official Google voice app. You may want to use the official Google Voice app.