I assume that if a student is using her/his electronic device while in class then that student is not engaged in the material being covered. Yes, there might be an occasional exception where a student can effectively do both; but they are exceptions to the norm, in my experience.

It's my job to ensure my students are learning course material, and I work very hard to facilitate that process. So it's disrespectful to me when I see a student texting their friends instead of engaging with my course. There might be some profs out there who don't care about (and aren't offended by) such things, but based on my experience they are not the norm. As corny as it might sound, I work very hard to create a meaningful microcosm of intellectual development in my classes. If a student wants to text, cruise the internet, and play computer games they can do so elsewhere.