Amicu - Improve social habits by using reminders to keep in touch.
Shared Contacts For GMail - Share contacts and address books with your team in Google Workspace, previously known as G Suite, Gmail, or your mobile Contact app, just like you share Google docs!
Monica - Monica is an open-source personal CRM to keep track of your friends and family.
E-Z Contact Book - E-Z Contact Book is an easy to use yet powerful Windows application for managing contact information. You can use it as a personal contact address/phone book, business directory, or a customer database, or a reminder of birthdays and other events
ContactBook App - ContactBook helps your business organize and manage contacts centrally and keep them shared with the right people.
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.