東京ちかてつ案内 is an Android app developed by Masaru that provides information on all 13 lines of the Tokyo Metro and Toei Subway. This app displays the estimated transfer time and distance, as well as the optimal train car for transfers.

By tapping on the map at the top of the main screen, users can view the route map of the Tokyo Metro and Toei Subway. The map can be freely zoomed, scaled, and moved for better visualization.

When selecting the starting line (the line the user is currently on) from the main screen, users can then choose the transfer station from the list of stations.

The detailed station page provides a rough layout diagram, estimated transfer time, and the recommended train car for transfers. Additionally, users can easily access the official websites of the Tokyo Metro and Toei Subway, as well as Google Maps, with just one button.