Create an app that lets the metro riders rate the commuting experience in real time. These ratings should be used to re-train the operators.
A lot of metro problems are not just technical; they are related to the competence of train operators. Many operators create a roller coaster experience for the commuters by closing the doors too quickly (which often leads to trains being off loaded), stopping just before the station and then suddenly starting with a jerk, not pulling a train all the way to the front of the platform among others.
This app would allow riders to rate the operator in real time. These ratings would be used to re-train the operators and improve their performance on key indicators.