We discovered an issue with the version of the iPhone Google+ App that was on the App Store. When we launched, the App Store started serving a previous test version of the App which didn't have the stability and fixes that the latest version had. It started serving the correct version a little later. If you downloaded within the first 1 hour 40 mins, you may have downloaded the older test version.
To check:
- Click on the gear icon on the top left of your App's homescreen and look right above the Help button, the version number of the App should be: 1.0.1.1809

- If that is not the version number, then please uninstall and reinstall by clicking on the link below:
http://itunes.apple.com/us/app/google/id447119634?ls=1&mt=8