Just caught this on Slashdot:
Free IMAP on Gmail
We use Google Apps at Concrete Websites, so I thought I’d check, and – lo and behold – we have it! You have to check your account’s settings tab, and if you’re lucky, you’ll see Forwarding and POP/IMAP (it used to just be POP.)
Once I confirmed that this option was available, it was a matter of five seconds before I retrieved my iPhone, and attempted to get my Google Apps email account integrated into it – hoping that IMAP access would end all manner of painful interaction between the phone the Gmail account (much of which has been recounted elsewhere.) Fortunately, Google has a helpful page that lists connection information for a variety of platforms – including, yes, the iPhone .
So far I’m pretty impressed. Deleting messages in the iPhone deletes them nearly immediately in Gmail. Your various labels are reflected as IMAP folders (including All Mail, allowing you to keep your mail nicely archived while still using your iPhone.) I’m looking forward to being able to go back to using Apple’s Mail client, which I’d abandoned due to the difficult nature of sharing multiple POP clients with one POP mail account.