PowerSchool - PowerSchool provides a K-12 education technology platform for operations, classroom, student growth, and family engagement.
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.
Teachable - Create and sell beautiful online courses with the platform used by the best online entrepreneurs to sell $100m+ to over 4 million students worldwide.
FullContact Card Reader - Automagically scan biz cards into LinkedIn/Gmail contacts
Clever - syncing between education applications for K-12 schools
Nextcloud Contacts - The Nextcloud contacts app is a user interface for Nextcloud's CardDAV server.