There is an aclu app called mobile justice that does this. There appears to be a different one for each state. I was previously under the impression that it uploads the video if you shake your phone, but I found some articles that suggest it transmits while you’re recording.

>The app features a large red “Record” button in the middle of the screen. When it’s pressed, the video is recorded on the phone and a duplicate copy is transmitted simultaneously to the ACLU server.