Yahoo Mail is adding new contact cards that can display glanceable information about your contacts without having to leave your inbox. Hovering over an name in an email will activate the smart contact cards, which automatically pull in photos, phone numbers, job titles, and links to Facebook and Twitter profiles (to see information from Facebook, you'll need to link your Facebook profile to your Yahoo Mail account). You can also search for emails from the person or company, or compose a new email directly from the contact card. The new contact cards are powered by technology from Xobni, which Yahoo acquired back in 2013. Yahoo says the contact cards will gradually roll out to desktop users in the US.
Yahoo Mail adds smart contact cards to your inbox
Yahoo Mail adds smart contact cards to your inbox/
The feature is currently only available in the US