get.evercontact.comSoftware by Kwaga
CONTACTBOX - CONTACTBOX combines the simplicity of an address book with effective functions of a CRM system.
Kontact - Kontact is the integrated Personal Information Manager of KDE.
Pobuca Connect - Connect with your contacts.
Nextcloud Contacts - The Nextcloud contacts app is a user interface for Nextcloud's CardDAV server.
CRM-gx - Contact Management
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.