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.
XML Copy Editor - XML Copy Editor is a fast, free, validating XML editor.
FullContact Card Reader - Automagically scan biz cards into LinkedIn/Gmail contacts
Oxygen XML Editor - Oxygen XML Editor provides a comprehensive suite of XML authoring and development tools.
Nextcloud Contacts - The Nextcloud contacts app is a user interface for Nextcloud's CardDAV server.
Liquid Studio - XML Tools Provider: XML Studio - Graphical XML Schema Editor.