A server maintains a gallery of ephemeral messages. Each ephemeral message is posted to the gallery by a user for viewing by recipients via recipient devices. In response to a gallery view request from any of the recipient devices, the ephemeral messages in the gallery are displayed on the requesting device in automated sequence, each message being displayed for a respective display duration before display of the next message in the gallery. Each ephemeral message has an associated message availability parameter, at the expiry of which the ephemeral message is made unavailable for viewing as part of the gallery. At expiry of the message availability parameter of the last posted message, the gallery is made unavailable for viewing upon request by any recipient.