PostGrid has been great for automating our insurance mails for our client
Lob - A simple API to integrate print & mail solutions into your applications.
Polymail Sequences - Simple, powerful multi-stage email campaigns
Postalytics - Automated direct mail software that’s faster, smarter & better. Postalytics sends personalized direct mail from your CRM and analyzes delivery & response.
MailChimp Snap - Send simple, photo-based email campaigns from your phone.
AmazingMail - Business print-mail solution
Mail Blaze - Your Success is our fuel