We have a few agreements. No phones on dates, during meals, during family time, in bed, in shower (we shower together).
This is true for BOTH of my relationships and actually-most of those are "no electronics" not just no phones.
It is one of the ways we help "stay in the moment" experiences for our lives. These aren't "rules" that we enforce on each other, but preferences we have agreed to through experience, trial and error.
And-I have to say after a year of living by these expectations, we are all happier for it. Not only in our romances, but in our lives as a whole.
"Love As Thou Wilt"