Does anyone know how to change the icon next to the email in Yahoo's new interface? I would like to change it to my company's logo or lettermark, but I can't find any information on how to do. Here's an image of what I'm talking about (sorry for the large size):

You can see the avatar-type image on the smaller tablet on the right (über logo) and in the email on the left. I'm seeing this new style in my Yahoo mail apps on both my iPad and Android phone. I feel it would really help with the branding of the company.

Any help or articles that talk about this would really help me out.