NextMuni, used to predict arrival times of buses and trains, ran on AT&T's 2G network. Muni vehicles without upgraded systems installed don't show up on NextMuni, a problem that the San Francisco transit agency believes could take weeks to solve. AT&T Shuts Down 2G Network and Ends Cellular Connectivity for Original iPhone - Mac Rumors まずはまだ2Gで動いているシステムが残っていたことが驚きです。 が、機能が十分に満たされていたのであれば置き換えしないでおく