I bet there was a debate about using paper originally as opposed to the traditional oral method. Times change, and having the Bible at our fingertips like that is a great thing. So I don't hold it against anyone using it like that - just please make sure the ringer is off?
I don't disagree in what you say but it does distract others with them flashing and fingers moving. We could say but that's your problem if you can't focus but then where is the concern and love for our family. Secondly I have seen personaly where people start to do other things like texting, emailing and even croping pictures. We have to be very careful where we go with the use of technology.
I agree there does need to be caution in our use of technology, why are we doing it? Will it be beneficial? As long as it is used with others in mind and in using it to read the Bible during sermons and not texting or surfing the internet, then there is no harm. But if you are tempted to text or surf or more, then by all means... "If it ain't Jesus calling... shut it off!" (From The Fighting Temptations movie).