I don't know about your phone, but my Sidekick 2008's calendar is useless to me, especially since I use Google Calendar.
When I'm out I use to have to write down an event on my hand or in a notebook, use the useless calendar on my phone, or go to www.google.com/calendar/m on my phone's internet browser. To make things a lot easier I can send a text message to Google Calendar.
The first thing you have to do is set Google Calendar up with your mobile phone.
1. Go into Settings up in the top right hand corner of Google Calendar.
2. Choose Mobile Setup.
3. Set up your calendar for your phone, a text message will be sent to you with a Verification code.
4. Put in the Verification code into Google Calendar, then click Save.
Now you can start adding events to your Google Calendar straight from your mobile phone.
To add an event to your Google Calendar from your phone send a message like Dinner 5:30 Tomorrow to 48368 (GEvent).
Now your event will be added to your Google calendar; however, the event is automatically set for all day.
This works like a Mobile Me if you are using Mozilla's Thunderbird and Lighting. See this tutorial on setting up your Google Calendar in Thunderbird.
Along with adding events straight from your phone, you can also have Google Calendar send your phone notifications, request your calendar for the day and have Google email your calendar to you each day.
To set up a notification:
1. Click on a day to add an event like normal.
2. On the pop-up choose Edit Event Details.
3. Fill out your event.
4. Under Options go to Reminder and select SMS instead of Pop-Up.
5. Select when you want to be reminded and click Save.
To request your calendar:
Send GEvent a text message with:
'next' to view your next event
'day' request all of your scheduled events for the present day
'nday' request your events scheduled for the following day
To receive your daily agenda:
This is something I highly recommend, but you first have to set your email up on your phone.
1. Go into Google calendar settings up in the top right hand corner.
2. Choose Calendars.
3. Choose the calendar you want to have sent to you daily.
4. Choose Notifications.
5. Check mark Daily Agenda.
There are also some other options you can choose in the Notifications option.
So there we go, how to utilize and take advantage of Google Calendar with your mobile phone.