Microsoft have finally released the expected update to the Windows Mobile OS for portable devices
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The most significant changes to Windows Mobile 6.1 Standard (previously known as Smartphone) are:

- New larger system font (Causes some third-party applications to render texts incorrectly)
- Sliding Panel home screen (A scroll wheel is much appreciated now)
- Threaded messages (Conversations-based as on the iPhone)
- Number of characters left counter now available in the title bar (Nice and neat.)
- Can't mark messages as unread anymore (It's a mystery to us.)
- Multiple message select is available (good job!)
- The default email signature now says "Sent from my Windows Mobile phone." (sounds iPhonish again)
- Start button can either open the new "Recent programs" listing or the usual "All Programs" folder
- Pocket Internet Explorer has a new Zoom feature (Compensating for the lack of a mini-map)
- Copy/Paste text function (It was about time! Anyways, it's available in Internet Explorer, Messaging, and Office only)
- New Clock&Alarm menu in the "All Programs" listing for easier managing of Alarms
- New "Managed Programs" item in settings for all apps installed remotely by your company Sys Admin

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The Professional version of WinMo 6.1 doesn't have that many updates.
However there are still some things such as:

- Internet Explorer: You can Zoom Out to see the web page overview (It's not available while the page is loading and the text is mostly unreadable, so it's just a mini-map alternative.)
- Internet Explorer: The "Text Size" menu is now "Zoom Level" menu (Resizes both pictures and text now.)
- There's a better native Task Manager and it's more easily accessible (Can also be assigned to a hardware key and it also shows system processes)
- New "Managed Programs" item for all apps installed remotely by your company Sys Admin
- The Calendar still has the useless greyed-out "Reply" command all over (Hello, is there anybody there in Microsoft?)
- SMS messages now show threaded as conversations
- Replying text messages has a new instant-messaging-like interface
- Can't mark messages as unread anymore (For reasons unknown to mortals!)
- Delete does away with entire conversations
- The time the messages have been received only shows up if the message was received today

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The Windows Mobile 6.1 won't be available for direct purchase to existing devices. Instead manufacturers will take care to release it as a free update to selected device. It's good to know that there are already several devices out there that will use the 6.1 version out-of-the-box. Among those are:

ASUS: New phones including the P320, ZX1, P560, M536 and updates for the P527, P750, M930
HTC: A new Touch Dual for the U.S. and updates for the AT&T Tilt, Touch by HTC, Mogul by HTC from Sprint, TyTN II
i-mate: 8502, 9502, 8150, 6150
Motorola: MOTO Q 9c, MOTO Q 9h global
Samsung: BlackJack II
Toshiba: Portege G810, Portege G910