I think you are making a joke but it is the latter case. He see you using it so he knows it must be important! and his primary tool for figuring out the world is his mouth!
I actually think it might be the former. There's a famous study where parents put on a completely flat face for a few minutes and denied their infants any attention. The babies reacted extremely poorly. I wish I could remember the name of the effect & the study so I could link it but the name totally escapes me
Anyway, point being, they did the same study but with parents using smartphones, and babies reacted in exactly the same fashion (distress)
