By default iPhone 3G is configured to check emails only manually. To make it check email regularly the change in the settings needs to be made. Since I spent more time than I expected finding out how to make iPhone 3G check email periodically, I decided that it's worthy a post. I was looking all over Settings | Email, Calendar and Contacts, where I thought the setting would be, and could not find it. Instead it turned out to be Settings | Fetch New Data. That what drives frequency of email checks:
