SEATTLE — In the middle of a long bicycle ride several weeks ago, I pulled over for a rest and took out my iPhone to send a text message to my wife. I had a feeling she might be watching me.

“If you’re checking my location, I’m not dead,” I wrote to her. “I’m getting coffee on Mercer Island.”

As it happens, she was not keeping tabs on where I was, but she could have — and has in the past — because I have allowed her to do so using the location-tracking capability in my phone. Whenever she’s curious, she can see me represented as an orange dot on a digital map on her phone. An unmoving dot could be a cyclist husband who got a flat tire, grabbed a beer with a friend or was hit by a car (hence the reassuring text).

Now and again, I, too, check my wife’s location so I know when she leaves work and can time dinner with her arrival. She and I have both tracked the whereabouts of our 13-year-old daughter using her phone to reassure ourselves that she was on her way home from school or a trip to the store.