Microsoft recently confirmed that it would be updating many of the built-in apps in Windows 8 between the release to manufacturing (RTM) of the OS and its general availability on October 26. Here’s a peek at the changes the firm just made to its Metro-style Mail, Calendar, People, and Messaging apps.

I wrote about this app updating confirmation in Windows 8: Updates Coming to Built-In Apps after having been speaking about (on podcasts) and writing (here and in Windows 8 Secrets) for months about Microsoft’s plans to do just this.

Note: The Mail, Calendar, People, and Messaging apps are connected together and installed as a single package. As such, this will be one of the more complex updates to document, so please be sure to let me know if you see any changes I’ve missed.

Here’s what’s new in the Mail, Calendar, People, and Messaging apps.

Mail: Conversation view

In the RTM version of the Mail app (build 4206), messages in a single email thread were disconnected and just appeared in the order they arrived (with the newest messages at the top of the message list). In the new version of the app (build 4391), Mail now sports a Conversation view, like Outlook and Office 365, in which messages in a single thread are grouped together, such that the entire message thread appears in the message list together. You can click a single message to expand and collapse this Conversation view.

When collapsed, the latest message in a conversation will denote the number of messages in the conversation:

mail-collapsed

Click that message to expand the conversation.

mail-expanded

Mail: Complete IMAP account support, POP support

Where the “Other account” type in the RTM version of the Mail app let you connect to IMAP-type email services, the new version explicitly supports both IMAP and POP email accounts.

mail-accounts

Note: It appears that POP support isn't currently working. That will be coming in the future.

Mail: Accept and decline meeting invitations

The Mail app now supports accepting and declining Exchange-type meeting requests (similar to how the Windows Phone Mail app works.)

mail-meeting-request

People: Change your account picture

The People app now lets you change the picture associated with your Microsoft account. Just click the Me tile under Social, then click your account picture from the Me view. (In the RTM version of People, this did nothing.)

people-change-acct-pic

Messaging: Contact search

In the RTM version of Messaging, you could click a New message button and then use a People picker to select a contact. Now, there is a search box next to the New message button that lets you search for a contact without leaving the app, and it offers auto-complete.

messaging-contacts

Calendar?

Microsoft did not list any changes to the Calendar app. I see a new tile color (for whatever reason). (It used to be navy blue.)

calendar-tile

And Charles V. points out that the calendar selector in the new event screen is different and is now a more obvious drop-down list.

calendar-choice

Is there more?

Have I missed anything? If you see any new features in the Metro-style Mail, Calendar, People, or Messaging apps, please let me know and I’ll update this article.