Microsoft has finally added IMAP support to Outlook.com, more than a year after the service was unveiled as the successor to Hotmail. The feature, available immediately and in tandem with OAuth, gives third-party developers another option when it comes to syncing messages and folders from the service.
Although the IMAP protocol is older than Microsoft's preferred method of email sync, Exchange ActiveSync (EAS), it's still a widely supported protocol, especially on feature phones and Mac OS email clients. Microsoft's Steve Kafka writes "we heard your feedback loud and clear that this was important", and announced the tighter integration Outlook.com in certain apps, including TripIt, Sift and OtherInbox.
IMAP (an abbreviation for Internet Message Access Protocol) was first designed way back in 1986 as a remote mailbox protocol, although it has been developed and improved on since the first iteration. One of the key features of IMAP is its robust folder system, allowing users to manage their emails in the hierarchy and setup that they prefer.
Gmail has supported IMAP since late 2007, and although the company offered EAS syncing options, last year it was announced that EAS support would be phased out, much to the annoyance of Windows Phone users. Gmail now primarily uses IMAP, CardDAV and CalDAV to sync emails, contacts and calendars respectively.
While Microsoft has now included IMAP support in Outlook.com, it still recommends using Exchange ActiveSync wherever possible. However if you do want to setup a third-party client to access Outlook.com through IMAP, Microsoft has listed instructions at the bottom of their blog post.