It's not a brand-specific phone issue.   I have an HTC Incredible and my husband has a Samsung and neither are updating properly.  It's incredibly frustrating to change a time on an appointment and not have the mobile device update.  Being that this has worked properly for me for over a year and has just recently become a problem, I was hoping someone at Google would be looking into it.  Does anyone in a tech support capacity actually read these issues or our we just grumbling amongst ourselves?