The feature allows friends and families to collaborate on photo albums. Users can subscribe to albums and receive notifications anyone adds an image to the album. You can also send out invites for collaboration, as you would with Google Docs.
Google’s also added the ability to label people on your albums. These labels can be customized, so you can call your friends and families by nicknames if you prefer, such as ‘crazy uncle’ or ‘pizza buddy’.
Photos is also finally getting casting support now, meaning you can send over animated GIFs to the fancy new Chromecast. This should make it a lot easier to stream slideshows across screens and share your litany of images with a group of people. You can also set images as backdrops for your Chromecast as well.