There used to be a time that when you saw someone different and that made you feel uncomfortable, you more or less had to keep it to yourself. Now you can report "suspicious people" from apps on your smart phone! How neat is that? You may find it odd that an overwhelming majority of those people who are reported as "suspicious" happen to be people of color, but.... Well, there's really no excuse for that.
Things we mentioned:
Georgetown's app for "suspicious people": https://www.washingtonpost.com/local/social-issues/the-secret-surveillance-of-suspicious-blacks-in-one-of-the-nations-poshest-neighborhoods/2015/10/13/2e47236c-6c4d-11e5-b31c-d80d62b53e28_story.html
Carimah Townes' article in ThinkProgress: http://thinkprogress.org/justice/2016/04/20/3770695/st-louis-residents-to-use-uber-like-app-to-report-suspicious-behavior/