FullContact - Put the power of full contact information into your web or mobile apps.
Clearbit - Clearbit provides Business Intelligence APIs
Pipl - The most comprehensive people search. Pipl is the place to find the person behind the email address, social username or phone number.
ZoomInfo - ZoomInfo is a B2B database providing detailed business information on people and companies.
Evercontact - Your contacts always up to date and automatically with Evercontact.
InsideView - InsideView aggregates and curates all the company and contact data, news and social insights, and professional connections you need to do business better.