Instead of using Google or Apple to store your contact information you can use cloudjazz.

To get started log into cloudjazz via the web interface and click the contact icon in the top bar.

Then click "Settings" in the bottom left corner.

Click the three little dots next to the "Contacts" folder and click copy link.

On your clipboard you will now have something that looks like:
https://www.zzzzzzzzzzzzz.net/remote.php/dav/addressbooks/users/UserName/contacts/

You can use this URL to syncronise your contacts with any program or device that supports "CalDav" or by, for instance, installing DavX5 on your device.

The way you connect to your cloudjazz contacts will be a little different for each program and device though the principles are the same.

Syncronise contacts with your devices

• Android
• iOS
• KDE Kontact
• macOS
• Thunderbird
• Windows10

You can also enter your contacts in manually or import your contacts using other methods.

See the NextCloud documentation for various methods:
https://docs.nextcloud.com/server/stable/user_manual/pim/contacts.html