SendX.io - SendX (https://sendx.io) provides remarketing and retargeting tools for web businesses. You can use popups, landing pages, email, web push notification, automation workflows and FB / Google retargeting to drive more revenue.
NeverBounce - Real-time email verification and cleaning to ensure emails never bounce.
MailerLite - Affordable Email Marketing Software. Get all features (Segmentation, Automation, A/B testing) for up to 1,000 subscribers & send unlimited emails for free!
Email Verifier - Email verifier app lets you verify email.
ConvertKit - Email marketing software for online creators. We help you earn a living online through an intuitive email marketing automation tool.
Verimail - Clean up email-address lists of any size or use our powerful API for real-time verification.