Sync Google Apps Calendar to my iPhone

I have a Google Apps account through work. I've noticed that when I add a calendar event there is a significant lag time between when I add the event and when it appears on my iPhone. Additionally, edited events don't seem to be reflected on my iPhone. Is there a way that I can ensure that events are added and updated in a timely fashion?

From web app Justin Gallagher

• On the iPhone under Settings->Mail... go into Fetch New Data and turn on Push.

  Justin Gallagher : I already have push turned on.
  From nevster

• From http://www.google.com/support/mobile/bin/answer.py?hl=en&answer=151674:

  To sync with your device, follow these steps:

  1. Open the Settings application on your device's home screen.
  2. Open Mail, Contacts, Calendars.
  3. Select Add Account...
  4. Select Other.
  5. Select Add CalDAV Account.
  6. Enter your account information: * In the Server field, enter [ google.com ] * In the Username field, enter your full Google Account or Google Apps email address. * In the Password field, enter your Google Account or Google Apps password. * In the Description field, enter the name you'd like to appear on the account.
  7. Select Next at the top of your screen.

  After you've completed setup, open the Calendar app on your device and syncing will automatically begin.

  By default only your primary calendar will be synced to your device. You can sync additional calendars by visiting the following page from any web browser:

  * https://www.google.com/calendar/iphoneselect
    (Google Apps users can go to https://www.google.com/calendar/hosted/your_domain/iphoneselect, replacing 'your_domain' with your actual domain name.)
  

  Select the calendars you'd like to sync, and click Save. The selected calendars will display on your device at the time of the next sync.

  666damo : Personally, I used the Exchange ActiveSync method with my iPhone. http://www.google.com/support/mobile/bin/answer.py?hl=en&answer=138740

  Justin Gallagher : Is this different than adding my Google Apps account as a mail account and switching the "Calendars" option on in the settings panel?
  From 666damo