Someone in my family has got a habit of reading or watching something on mobile during eating. He just cannot eat without doing that but if i can show him that Islam abhors it he will change. So please let me know any hadees etc to show it is not good to do things while eating

We should give respect to the rizq which Allah has provided us therefore doing something else at the food table while eating shows our negligence to the food also showing disrespect to whom who has prepared the food. Because it is good Akhlaq that we should praise to whom who has spent hours and prepared food for us.
There is certain etiquette to be observed at the dining table. Starting with the name of Allah; eating with the right hand; making small morsels; sitting longer at the table; chewing the food well; thanking Allah after the food; washing the fruits and vegetables before eating; not eating after satisfying the appetite; not over eating; not looking at the faces of others while eating; not taking away the food from others who are sitting at the table; and tasting the salt at the beginning and the end of the dinner.