Most of the time, they're reading, some are playing games in their smartphones, and obviously, some are plugged in with their headphones listening to music. It's interesting how technology allows one to create a virtual private space, such that even in a cramped subway car, one can still be in relative solitude.
Normally, I would mind these artificially-created solo moments. I just find it very impersonal. This is me who normally prefers real humans to automated tellers and self-checkouts in society. However, sometimes, I feel that it is more of a survival defense mechanism that people create these virtual solo spaces.
Most of the time, I think of this in the context of the buskers that ride the metro. I have seen performances of the same person in the train, one at the outbound, and another when I was coming back. I feel a little uncomfortable watching these performances, as it is, I am forced to watch these, and I am pretty much a captive audience. I am forced to hear their loud salsa music even though I didn't choose to listen to it. Hence, I can see how people would want to just keep the outside noise out by creating this virtual space that only they can enjoy.
But then again, I'd rather have these buskers do what they are doing right now, than simply begging for spare change. If this is their idea of work, then so be it.
See, I still have a love-hate relationship with New York City.