AT&T and T-Mobile have signed agreements to allow their subscribers to access Transit Wireless’ underground cellular network in New York’s subway systems, Bloomberg reported Friday.

I wrote about public wifi in a mini-essay three weeks ago, but one related tangent I didn’t mention was the state of subway cellular access: on the Yokohama municipal subway line, cell phone users get cell coverage in the stations and hop from station to station like lit-up islands in a dark abyss, quickly downloading webpages and making their calls before their trains take them away from the station and head to the next. In some segments of some lines in Tokyo, the scene is better: cell phones in some parts of some lines don’t lose reception even when they leave a station and enter the aforementioned abyss. In comparison, Korea gets cellular and wifi coverage downstairs, along with Spain, Portugal, Singapore, Taiwan, Italy, and Chicago, Illinois; with London on the way.