I have reasons to believe that my sister works like this. We joke that she has "office hours". She will rarely answer messages or calls that she does not expect right away. Then at around eight in the evening, every other days or so, messages will start trickling in.

At first it was a bit annoying, but once you know that she works like that it perfectly fine. I'm starting to think that she's doing modern communication correct.

Knowing there'll be a delay in response if you text also makes using your phone as a telephone have value again, too...