There are "no cell phone" posters up in the gym, but not in the spin room. I guess they could be using it for data. Since I gave up on data years ago (except for how many miles I've ridden and a quick look at my average, when I am outside), I really didn't think of that. I should, though, as all the little blinking green lights from people who have their Fitbits attached to their shoes in spin class might be enough to give someone a seizure. Our spin bikes give watts, which I also pay no attention to.