The next version of Windows Phone 7, called “Mango,” although that won't be its final name, is great-looking and fun to use. It's full of people-centric features that make it easier to stay in touch with friends and family, to communicate, and to share ideas. It's easier to use than Android, and in many ways slicker than Apple's iOS.

Microsoft lent me a Samsung Focus loaded with a developer build of Windows Phone 7 Mango, which isn't yet complete. Still, the developer build let me get a feel for which features will really pop, and which still need work.
For a rundown of the basic features of the OS, check out our Windows Phone 7 review. You might also want to read our review of the Samsung Focus, the best Windows Phone so far.
Mango will appear this fall, both as an upgrade for current Windows Phones and on new devices, Microsoft says.
Windows Phone 7 has always been activity-centered rather than app-centered. Its hubs let you focus on ideas like “people,” “pictures” or “music” rather than about which particular app or service you need at the moment.
My favorite new Mango feature is the new Groups option in the People hub. With Facebook and Twitter added to your phone book, you're probably going to have a lot of contacts. Groups help you make sense of them. I don't use Facebook because I find it overwhelming. With my account stuffed full of acquaintances, everyone I went to school with, and people from work, my news feed is a massive flow of data from people I hardly know.
Windows Phone Mango makes me want to use Facebook again. I set up a Family group and saw only the updates and photo albums from my family; a Work group showed only updates and photo albums from colleagues. We move in multiple circles, and Mango lets your phone reflect that.
Facebook pops up everywhere. You can take a picture by pressing the camera button straight from the lock screen, auto-tag it with names, and share it on Facebook. The Calendar absorbs Facebook events, complete with their walls and commentary. The photo gallery lets you immediately dip into your friends' Facebook galleries. It's safe to say Mango is the most Facebook-oriented OS available in the U.S.
Email and office tasks have all received a bit of a bump. There's a useful conversation view in email, and you can more easily start new calendar entries by typing directly into a calendar line. The Microsoft Office apps now automatically connect to Skydrive, which gives you a decent way to get files onto your phone—you still can't drag and drop files from a local PC, though, which is frustrating.
Multitasking is just fast app switching, for now. Hold down the Back button, and you can flip between your most recent apps, each paused where you left them. That's a start, but it will take new apps written with new APIs to actually start doing things in the background, including using background data to update home-screen tiles.
Bing Vision is a Google Goggles clone, letting you search for objects by scanning barcodes to return Web and shopping results, or translating text between languages. It feels a bit like a gimmick, and I had trouble testing it because of a bug that kept throwing the camera out of focus in macro mode, making it unable to scan anything. Ah, beta software.
The new voice-to-text features are flashy, though I'd prefer if they went further. You can dictate text messages and search for items on the Web using voice commands, and it takes that voice input from a Bluetooth headset - great! I'd like it even more if you didn't have to periodically press on-screen buttons as part of the process.
(Source: PC Magazine)