Gmail Mail Merge - Send personalized emails with attachments
Nova Inbox - Personalize emails in seconds, right from your inbox
Tropical.io - Connect your CRM and other sources (Mailchimp, Unbounce, GoToWebinar, Uservoice, and more) and we tell you which leads are hot
InboxSDK - First usable API to write Gmail Apps for 1B active users
PushMarket - Automate personalized emails for ecommerce (YC15)
Amazon SES - Scale your business email & marketing messages with Amazon Simple Email Service (SES), a cost-effective and reliable cloud email service. Sign up today.