As the system is still in beta, it currently has limited aromas registered in its database, one of which is the notable "wet dog" smell. Others include the smell of metal and onions.
Expect more from Google Nose in the coming months. This technology would probably be integrated to Google Glass in the future. To know more about Google Nose, visit https://www.google.com.ph/intl/en/landing/nose.
The Google Nose Beta requires the latest version of Chrome. It's also one of the more entertaining April Fools Day pranks of the company aside from the YouTube shutdown.