OneLogin - On-demand SSO, directory integration, user provisioning and more
Google Contacts - Google Contacts is Google's contact management tool that is available in its free email service Gmail, as a standalone service, and as a part of Google's business-oriented suite of web apps Google Apps.
Okta - Enterprise-grade identity management for all your apps, users & devices
Free Address Book - In our contact management software you can store fast and easily name, phone numbers, birthdays, address, company name, city, mobile numbers, insurance and loan info, e-mail addresses.
PortalGuard - A dedicated web-based identity management portal that combines strong authentication with flexible, high-performance integration.
Clearbit - Clearbit provides Business Intelligence APIs