Here's our pick of the most useful and interesting apps from Microsoft's Windows Phone 7 Marketplace hub
Category: News and weather
Puts a local weather summary on your home screen, updated immediately via the Windows Phone 7 push capability, with such information as severe weather alerts. Rated 4 out of 5 stars by users who like that the 'live tile' approach keeps the information current on the phone's start screen. Some said it can be slow starting, and when switching between cities for information.
Category: Music & video
There's a debate whether this is really an app: essentially, you click on the icon, and it redirects you to the YouTube mobile site for mobile users, through the greatly improved mobile Internet Explorer. Users slam it as 'lame' but it's won 3 stars for doing "the job of bringing YouTube to Windows Phone" and for good streaming performance.