I use a combination of Nextcloud Talk (for 1-on-1 conversations) and Jitsi Meet (for larger groups) with my 82yo mother, she has NC Talk and Jitsi on her phone

I use a combination of Nextcloud Talk (for 1-on-1 conversations) and Jitsi Meet (for larger groups) with my 82yo mother, she has NC Talk and Jitsi on her phone and tablet and access to both through the browser on her laptop. We use Telegram to schedule meetings through Jitsi Meet or for those cases where NC Talk doesn't notify the called party that someone is calling. It works fine, we use it for ~30 minutes per day, every day.