13 honest alerts every transit apps needs

You need to know what time the train leaves and where it's headed. Thankfully, there are a variety of apps to help you do that.
But wouldn't it be great if the apps told you what you really needed to know? Which train car is too crowded? Which line is going to randomly go express?
SEE ALSO: The 'Subway Idiot' is back, and he's running for love
Here are some features we'd love to see added to transit apps. Read more...
1. A notification stating which train car has a loose bottle rolling around.