V12 Data - V12 Data offers rich data sets with verified addresses and emails for personalized marketing campaigns.
Klaviyo - Klaviyo helps brands own the customer experience, grow higher-value relationships, and deliver more personalized marketing experiences across email, mobile, and web.
Lotame - Make your data actionable, learn about your most valuable customers, improve ROI by targeting the right audience and increase relevance across screens.
Criteo - Build, scale, and activate first-party audiences with The Commerce Media Platform.
Google Audience Center - 3 votes and 6 comments so far on Reddit
Campaign Monitor - Email marketing software built for designers and their clients to run successful email campaigns.