Do Shared Album contributors need to create a Memento account?

Contributors to Shared Albums do need to create a Memento account in order to share or view photos and videos. 

The first time contributors share photos/videos, they will be prompted to create a free account. This serves multiple purposes. First, it helps the organizer know who has uploaded photos & videos. Second, it lets the contributor know that the upload was successful. 

Don’t worry — when a contributor creates an account, they will not be required to sign up for a paid membership.