MailChimp - MailChimp is the best way to design, send, and share email newsletters.
ZeroBounce - Removes invalid emails from your list to prevent email bounces from ruining your deliverability.
Email Verifier - Email verifier app lets you verify email.
TheChecker.co - Accurate email verification at low prices.
NoBounce Email List Cleaner - Email list validation & cleaning maximizes the efficiency of your email marketing campaigns and protects your email sender reputation.
Sparkpost - Deliver your app and website emails on time and to the inbox. Trusted to send 25% of the world's non-spam email. Email delivery for companies big and small.