We have just released Mailster v1.5 which brought many new features towards helping our customers to run their operations in a GDPR compliant way.
This post gives you an overview of the improvements, the full list of changes can be found in our Mailster v1.5.0 changelog entry.
Starting with this version, all the subscription actions are recorded to a log database. The idea is that this can serve the mailing list operators for audit purposes.
It stores subscription information like who joined when to which list using which email address (and IP address).