Free Download Urban Air 2.1.0.1 XAP for Windows Phone
Free News & Weather App by Microsoft Research

You are downloading the Urban Air XAP file v2.1.0.1 for Windows Phone. Urban Air is a free and useful News & Weather app: The app provides a user with real-time and fine-grained air quality throughout a city. A user can monitor arbitrary locations (such as her current ... You can now download the offline XAP file to install & try it.
Download Locations for Urban Air 2.1.0.1 XAP file
Note: To install it manually from an SD card, you should choose one of the server location above to get the offline Urban Air XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.