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.

Outlook Google Calendar Sync - Offers calendar synchronisation between Outlook and Google, including attendees and reminders.

Nextcloud Contacts - The Nextcloud contacts app is a user interface for Nextcloud's CardDAV server.

AkrutoSync - Sync your Outlook contacts, calendar, tasks and notes on your PC direct with your phone via Wi-Fi or a cellular network.‎Buy · ‎FAQ · ‎Contact Us · ‎SupportPeople also askWhat is Akrutosync?

Microsoft People - People in Windows 10 puts all the ways you connect with all your friends, family, colleagues, and acquaintances in one place, so it’s faster than ever to keep in touch.

DAVx5 - DAVx5 is a CalDAV/CardDAV management and sync app for Android.