imapsync - Console-based utility for migrating IMAP mailboxes.
Google Tag Manager - Google Tag Manager helps make tag management simple, easy and reliable by allowing marketers and webmasters to deploy website tags all in one place.
audriga Email and Groupware migration - Easily migrate your email, contacts, calendar items and tasks to your new provider or server. No software installation is required.
Segment - We make customer data simple.
MailStore - MailStore Home - A 100% free single-private-user desktop solution
RudderStack - Open-Source Customer Data Platform