After finally removing Gmail's invite-only status and opening the service to everyone earlier this year, Google has added a little extra to keep users of mobile devices happy. As the company explains on the GMail "What's New" page, Gmail now supports external access to e-mail via the IMAP mail protocol in addition to POP.
POP may be a more popular protocol for non-Web-based mail delivery, but IMAP has the advantage of being server-centric (all mail is stored remotely, and local changes propagate to the server), making it better-suited for users who check the same mail account from multiple systems. IMAP is supported by major mail clients as well as mobile devices like the iPhone, which seems to be one of the targets of Google's move. The search giant has even put up a YouTube video tutorial to show iPhone owners how to set up their device to access Gmail via IMAP instead of POP.