Yahoo is adding a number of third-party apps and widgets to several of its properties, including the popular Yahoo Mail and My Yahoo services in a bid to increase the appeal of its Website by opening it up to other applications.

For Yahoo Mail users in the U.S., new apps include PayPal for sending and receiving money, Picnik for photo editing from your In box, MyPhotos for photo organization and sharing, and ZumoDrive, a file sharing service. These mail apps are only available for a limited number of users of the new Yahoo mail.

The move to open up Yahoo’s Web properties to widgets was actually begun during the reign of Jerry Yang, Yahoo’s co-founder who was replaced as CEO by Carol Bartz in January.

You can get the new apps here.

Yahoo has also announced new widgets for its Yahoo Connected TV service and for Zimbra, its email and collaboration tool.