cellphone etiquette

In the Sunday Styles this past weekend, etiquette guru Philip Galanes
tackled a tricky subject: the cellphone intervention. The basic
question being what to do when a friend is guilty of making so many
calls and complaining while you’re hanging out that you get to a point
where you want to put that friendship on an extremely long hold
(estimated wait time, 17 hours). Toeing that age-old line between
making new friends, but keeping the old, Galanes advises “there’s a
midpoint between suffering in silence and never seeing Cellphone Cindy
again.” He extols, “Speak up (kindly)!”
At what point does your phone etiquette make your friends start dropping off?