your realtime captioner is linda marie macdonald. now at 6:00, it is supposed to be a discreet way to report crime on bart. but one group says it could put you at risk. good evening, i'm ken bastida. >> i'm elizabeth cook in for veronica de la cruz. new at 6:00, phil matier on the new app that has privacy advocates sounding the alarm. phil. >> reporter: that's right, it goes on your phone and the idea is that it will allow you to collect information on what you might think is suspicious in and around bart stations. question is, while you're collecting the information, what's bart collecting on you? here's the story. >> choices through app itself or to call the bart police. >> reporter: it's called bart watch. and it's a new app that allows riders who see criminal unruly out suspicious behavior or bart trains to text on take a