Although personally, it struck me as very strange that someone who's just witnessed her partner being shot (and who is currently in some need of medical treatment) that her reaction is to reach for her phone and the live streaming feature of an app. I certainly think that falls under "evidence of an interesting new phenomenon".
Edit: I don't mean "strange" in any kind of moral judgement. My heart goes out to this woman and her child who had to witness this and who've lost someone close to them. I mean strange in the sense that this isn't how I would expect someone to react.
Police brutality has been a serious problem in the US for decades, and it seems that putting a streaming video camera in everyone's pocket might help shift the narrative back in the people's favor.