For friends/associates I use Whatsapp, but you could swap that with any other communication app that support voice calls... In fact I prefer that because then it's a known connection (I block unknown calls due to the large amount of SPAM I get in "normal phone calls"). It's the unknown callers (eg, return calls from contractors) that I haven't figured out, but there aren't enough of those calls for me to worry too much. My bigger concern are text communications. Several of my friends refuse to use Whatsapp and Teams... and I don't like/Trust Discord (what they want to use) so have to figure out something.