Key features:

• True per-list unsubscribe — members can leave one list while staying subscribed to every other list they belong to. Most mailing tools treat unsubscribe as all-or-nothing; Postrider doesn't.
• Native Community Builder integration — lists sync live from CB groups, with full merge-tag support for your existing CB custom fields (no separate contact list to maintain by hand).
• Listserv-style reflector/discussion lists — true post-and-distribute lists with reply-threading, not just one-way broadcast newsletters.
• Per-recipient delivery tracking — real open/click/bounce tracking per subscriber, not just an aggregate campaign summary.
• RFC 8058 one-click unsubscribe, built in natively for full compliance with modern mailbox-provider requirements (Gmail/Yahoo bulk sender rules).
• GDPR-conscious subscriber model — explicit opt-in records tied to consent, not silently harvested from your Joomla user table.
• Digest mode — per-list digest compilation and scheduled sending, alongside standard one-off campaigns.
• Familiar native Joomla admin UI for managing lists, subscribers, campaigns, and reports — no separate dashboard to learn.

Ideal for membership organisations, clubs, and associations already running Community Builder who need real segmented, list-based communication rather than a single blunt newsletter button.