Mailmeteor - Send hundreds of personalized emails with Gmail.
Trumail - Free email verification API
Mailazy - Modern Email Delivery API
Email List Verify - The Fastest Way to Improve Email List Deliverability and ROI
GMass - GMass allows you to easily schedule emails, send out mass emails and mail merge campaigns and more with Gmail! Click here to learn about more features!
Proofy - Quickly validate and verify your email lists.