I think that WP7 is one of the first phone operating systems which natively has a QR scanner built in.
It's rather hidden - you have to go in to search (not camera) then click the eye icon.
However, it is one of the fastest and most accurate scanners I've ever used. It knocks Android favourite ZXing into a cocked hat simply by by speed alone - it's also very fault tolerant and was able to scan in low light and at strange angles.
There's only one problem I have with it - the user interface really isn't very good. Part of this is the design constraints of the Metro interface, but that's no real excuse.
Let's compare WP7 and Android.
The scanner is quick and efficient - but doesn't let you see the whole destination URL.
Because it can barely fit in a whole bit.ly link, this could lead to some confusion when scanning: are you going to example.com/video or example.com/games for example.
There's also the (remote) possibility of a security problem; www.hsbc.com.evilsite.xxx will only show as www.hsbc.com
The layout of Android is quite different. I prefer the vertical arrangement of WP7 but Android provides better and more useful information.
(The screenshot doesn't show the camera view in the background.)
As well as the full URL, we're given
- The destination URL for any shortened URL.
- Sharing buttons.
- A bunch of extraneous techy stuff (meta data about the code).
It's often useful to go back and see what you have scanned. Both WP7 and Android have a history feature.
Again, WP7 looks gorgeous - especially with the photo thumbnail of what you scanned.
But, again, there's no way to see the full URL. And, again, the only thing you can do it click on it - no sharing options available.
Android is more Spartan - but more useful.
Although there's no thumbnail, we can see the full URL and any redirection. Clicking on a URL allows us to share it.
Windows Phone 7 has a faster and prettier scanner - Android has a scanner which has more useful features and presents less of a security risk.