I know a couple of people who use their phones to read the lyrics while they are actually playing a song. It doesn't bother me, nor does talking while I am singing or waiting to start. I think it is not possible to expect quietness from people in sessions as they are often held in public bars. There are places where you have to sing over the piped music or the background TV, especially when football is on (why people are so concerned with football is beyond me). I keep my phone on silent with vibrate and very rarely take it out of my pocket during a folk night. I do have to agree with Will Fly as I know several who only ever sing from a book or with the music in front of them (Complete with chord shapes) I find it strange given that they have a repertoire of only several songs which they trot out week after week. I am sure that for the small number of songs they sing, they could learn them off by heart. But you can get gigs in noisy places such as the odd rugby club with a noisy crowd and bar. Then it is just tough and you battle through. If you are able to capture the audience the atmosphere will spread and you can actually get listened to by the majority. There are always likely to be phones going off in public places. A few years ago nobody would have thought about holding a conversation with someone on the phone while sitting having a shit or pee in the bog, but I know it happens.