Although their not "state-of-the-art", The built in Mail, Calendar and People Apps, are a nice to have feature that comes with Windows 8.
They have very simple usage and are all connected with the Microsoft Live Services so with a Windows Phone you have seamlessly access to all the content.
Yesterday Microsoft launched an update to this 3 apps.
- Filter by All Unread e-mail
- Filter by Flagged e-mail
- "Smart contact suggestions" when writing a new e-mail
- E-mail search on server (hotmail.com/outlook.com) instead off local search, if needed
- Calendar view updated
- Work week view added
- New swiping from top (or right-click) to open the app commands
- New top navigation to switch between Facebook, Tweets, etc
- Filter by social network