Jess

I just dump the changes with timestamps to a text file. Notifications for IP changes get sent to matrix after the DNS record is updated.

This. Alternatively, share the link to URL Cleaner, unshorten it, and remove the extra junk. It’s an extra few steps, but worth it.

Signal is more likely to have more mass appeal. Matrix can bridge just about anything but is (IMHO) a pain to setup the first time. XMPP is reliable and available just about anywhere. I use the first two.

Ask your friends though.