Why is using a tablet any different from using, say, a guitar to help you perform a song? If someone got up to sing (from memory) with a guitar and didn't really know the chord patterns, stopped at several changes to position their fingers, and spent the whole time looking intently at the fretboard, that would be really awful (and I suspect most of us have sat through something like that more often than we would have liked!).

Same with a tablet: Used by people who do not understand the technology, have inappropriate software, and have not practised, it can be cringe-worthy. Used by someone who has put in the time to get to know the potential and uses, it can be almost invisible.