Optmyzr - Optmyzr AdWords Tools. Optimization Solutions, Quality Score Tracker, Landing Page Checker, and more. Free Trial Available.
Clearbit - Clearbit provides Business Intelligence APIs
Pathmatics - Pathmatics provides actionable display and mobile intelligence to many brands, agencies, publishers, and advertisers.
ZoomInfo - ZoomInfo is a B2B database providing detailed business information on people and companies.
Freshmarketer - An all-in-one CRO suite.
InsideView - InsideView aggregates and curates all the company and contact data, news and social insights, and professional connections you need to do business better.