Several people have asked me recently how e-mail on the BlackBerry works.
Here's a quick overview:
That stands for Blackberry Internet Service. It's the standard service that's available when you buy a BlackBerry and sign up for a data plan. When you get your phone, you go onto a carrier-specific website created by BlackBerry and link your e-mail account (GMail, Yahoo, whatever) to your BlackBerry. The BIS will grab e-mails from your e-mail account and "push" them to your BlackBerry. This service does not provide any sync feature. If you delete a message on your BlackBerry it will still show up on your GMail account, Yahoo account or whatever service you use. Also, BIS provides no sync for Calendar, Contacts or Tasks. Those need to be synced manually via cable or bluetooth between your computer and your BlackBerry.
BlackBerry Enterprise Server is software that is installed on top of a Microsoft Exchange Server (or Lotus Notes or other). It provides full sync service between the Mail, Calendar, Contacts and Tasks on your own computer, through the Exchange Server and to and from the BlackBerry. Clients that work with an Exchange Server--and therefore provide sync with the BlackBerry between your computer's data and your BlackBerry--include Outlook for Windows machines and Entourage for Macintosh. If you do have a BES, you can still make use of BIS for personal accounts. For example, you might sync your corporate Mail, Calendar etc. through BES but also grab your personal Yahoo mail through BIS.
Google has created two interesting alternatives to BIS and BES. They aren't as complete as BES but if you're a sole proprietor and don't want to go through the dramatic expense and hassle of an Exchange Server with BES, they're a pretty good solution. Go to the site that Google has established for BlackBerry applications (LINK) and follow the instructions to download to your BlackBerry the GMail program and the Sync program. With the GMail program on your BlackBerry you can have full bidirectional sync of ALL your GMail. The previous version wasn't all that usable because there was no off-line functionality, but now that they've added caching and an off-line capability for recent e-mails, I find that at least with my Verizon BlackBerry I'm able to dispense with the built-in BlackBerry e-mail application (except for SMS). Of course, you have to be making use of GMail. Further, the GMail application also provides access to your GMail contacts, in a limited way and without editing capability. Note that it doesn't make use of the built-in BlackBerry Address Book application but does it through the GMail BlackBerry application. Additionally, the Sync program does a beautiful job of synchronizing your Google Calendar.
Note that if you are a sole proprietor or a small team (or even a large team), it's likely to make sense to go with an outsourced Microsoft Exchange with BES option. You can check this out at Apptix, Intermedia or other hosting providers.
Unfortunately, there's no Google sync for tasks. BUT there is a great program called Remember The Milk (LINK) which does a bang up job of syncing your BlackBerry tasks with the RTM task management website (if you sign-up for the $25/year premium option). Further, if you use FireFox and GMail you can integrate your tasks with GMail.
All together now
If you want to get really crazy, you can use RTM and the Google Sync applications on your BlackBerry along with BES and produce full sync, via your BlackBerry, back to your Outlook or Entourage client. Best way I know of using Google Calendar and providing a seamless sync back to an Outlook calendar so that your corporate team can see your calendar via Exchange Server.
IMAP and POP3
If you're wondering about IMAP and POP3 on the BlackBerry, none of the solutions discussed above make use of either of those protocols. Essentially, IMAP is a protocol used by programs like Outlook, Entourage and many others to access e-mail stored on a server and sync it between the client computer and the server. POP3 is a different protocol that downloads mail from the server to the client machine but doesn't provide the sync capability of IMAP.
Google has updated their Sync program so that contacts are synced on a limited basis: LINK.