Yeah texting is probably the most annoying thing, because it is like a flashlight in your face, and it seems that people don't realize that others are also able to see the bright light.
Last summer at Les Mis, these girls in front of me kept texting, and I finally just leaned forward and read the texts, which made them uncomfortable enough to stop.
But then after the show, I took my phone out, and I had left it on and the ringer was on loud! That would have been really had if my phone had gone off after I just bugged other people about texting. That was the only and only time I left my phone on during a show, and it was because I took it out at intermission to make sure it was off, and I inadvertently turned it on while double-checking that it was off---I'm coo coo for cocoa puffs!