Today Google has released Google Sync, and clear cut way to sync your Google contacts with S60 devices such as the Nokia E71. Calendar sync is supported for other devices like the iPhone and Windows Mobile, but not for S60 unfortunately. Check out what Google has to say, and look for the text that I bolded...
For iPhone and Windows Mobile devices, Google Sync allows you to get your Gmail Contacts and Google Calendar events to your phone. Once you set up Sync on your phone, it will automatically begin synchronizing your address book and calendar in the background, over-the-air, so you can attend to other tasks. Sync uses push technology so any changes or additions to your calendar or contacts are reflected on your device in minutes. The connection is always on so you don't have to manually sync your phone after Sync has been set up. This means that when your colleague changes the time of the TPS report cover sheets meeting, you'll know about it right away.
Since Sync is a two-way service, you can make changes on your phone or in your Google Account. Your calendar and contacts are always up-to-date, no matter where you are or what you're doing. Also, since your data is automatically backed up to your Google Account, it's securely stored even if you lose your phone.
For devices that support the open SyncML protocol, Google Sync will allow for two-way contacts synchronization. If you're a BlackBerry user, a version of Google Sync is already available.
That little snipped that I put in bold is what applies to us, only contacts is supported.
I haven't tried this out yet as I'm not entirely sure that I need this functionality. I don't heavily rely on my Google contacts for my device, and if I do need something I just use the Gmail application.
Click here to learn more about Google sync for the Nokia E71. Click here to go straight to the instructions.
Sync Google Calendar & The E71
On the other hand, I heavily on Google Calendar. I've recently discovered GooSync thanks to E71 Fanatics Forum member hot_damn, at this post. I've been using it for a few weeks now and it works great. Everything is synced perfectly without any problems. It's free for the basic service, although they also have a premium service which I use. Click here to try out GooSync. I'll be giving a more detailed review in a couple of days.