AWeber - AWeber is an Email marketing software that's easy to use. Send email newsletters & autoresponders and deliver top notch emails.
Clearbit - Clearbit provides Business Intelligence APIs
MailChimp - MailChimp is the best way to design, send, and share email newsletters.
ZoomInfo - ZoomInfo is a B2B database providing detailed business information on people and companies.
ActiveCampaign - Integrated email marketing, marketing automation, and small business CRM. Send beautiful newsletters, setup behavioral based automations, and benefit from sales automation.
InsideView - InsideView aggregates and curates all the company and contact data, news and social insights, and professional connections you need to do business better.