I was stopped for essentially walking with books at 12:30 p.m. I was questioned for at least 15 minutes. He asked the weirdest questions. He looked through

I was stopped for essentially walking with books at 12:30 p.m. I was questioned for at least 15 minutes. He asked the weirdest questions. He looked through my books, and questioned why I had a old magazine on knitting. I actually told him why because I was kind of in shock over the nature of questions. I thought maybe he thought I was stealing mail? I told him the magazine is from the 80's, and didn't even have postage on it. Officer, "No--I was just wondering why a guy would be interested in knitting?" (The magazine was for a friend, and bought in a used book store) I thought about pulling out my iPhone and tapeing the encounter. I then realized the cop had his holster unbuckled, and no one was around, and he explicitly told me to keep my hands visable at all times. I'm not anti law enforcement. I'm just tired of being pulled over for no reason. Tired of expensive, dubious tickets, and courts that always side with the Officer. This has forced me to buy two dash cams(one in truck as backup--they are $15.00/unit from China, so I ordered two.) and I'm working on an app that turns on the smartphone video when ever the word "Officer" is mentioned. The scenerio I envision is I am walking down the street with the smartphone in my shirt pocket/jacket pocket(near enough to pick up my command of voicing "Officer" to wake up dormant phone, and turn on the video/audio app. If there is already an app out there, could someone point me in the right direction?