When my mom was still alive and relatively new to a smartphone (at age 80) I decided to send her some sort of relevant picture every day via Whatsapp, to get her used to communicating that way. Sometimes it was a real stretch to come up with something. But yes, this forces you to evaluate your life from that viewpoint "surely something was interesting today? Let's keep a picture of it". Even if it's just what I'm having for lunch that day.
But she's gone now and so is that habit.