Don't look at porn on the goddamn subway!
Although this should be common sense, it bears mentioning that you absolutely, 100% should not watch porn on the subway. This is non-negotiable. New Yorkers may proudly consider themselves unfazed, or perhaps even invigorated, by the nasty stuff they see every day, but that doesn't mean they should be subjected to watching you browse your favorite XTube channel during rush hour. Also, please wait until you get home to self-diagnose ailments and/or questionable moles on WebMD. We really don't want to see that, either.