As it often happens in very busy trains, people sometimes watch other people smartphones behind their back. Sometimes it is just out of curiosity, sometimes it is an event or something of interest.
I wish I could take a photo of this, but obviously I did not. A woman next to me was watching “Terrace House” on her smartphone, and I suddenly realized that two other women are standing behind her and watching with her. Obviously, they cannot watch it very well, but they were very interested in it. It looked like the best Commercial for Netflix.
A while back, I noticed a similar scenario with men watching a live feed of Japan National soccer team. About 3 men were doing extra effort to stay around a guy which had a live feed on his smartphone.