Enable ActiveSync when syncing contacts/calendars with mobile devices (including iPhone) with a Google Apps accountPosted by Chirag Patel in Insights
I followed the instructions to Google Sync with my iPhone, but the iPhone would do nothing even when I opened Contacts or Calendar on the iPhone. The issue was that the Google account was on Google Apps and not a regular Google account.
Turn on ActiveSync on Google apps with these instructions. Also see the below screenshot.activesync, google calendar sync, google contact sync, iPhone