Your "idea" is not entirely clear. But I Phones already have a "face time" feature that allows you to chat with the persons who you call (such as your children) and see their faces as you chat---this is perfectly legal. Further, if a GPS device was capable of watching your children from a distance, this would seem perfectly fine (although I am not sure how such a device would work). However, I must say that the thought that anyone could push a button and obtain a video feed from any location on earth so as to check on the safety of children (or for any other reason) frightens me, and seems to be an affront to basic concepts of privacy. This is the "big brother" nightmare that was at the core of George Orwell's 1984. In my view, this would violate our fundamental constitutional principles of liberty and freedom----in the wrong hands (such as right wing religious fanatics), such technology could be used in a discriminatory and unjust manner.
I was lead counsel in the Borings v. Google case, which resulted in the only known final judgment against Google as an *intentional trespasser* from their Street View program. Generally, whether there is a violation is often a question of consent. That is, whether the person agrees to be recorded or viewed in an areas where there is otherwise an expecation of privacy. Importantly, children cannot consent, but their parents must consent. Then, a parent may consent for the child, but, as a general rule, the recorded third-party must consent. You need to assume that not every person in contact with the child is a predator, and recorded third persons (in an area where privacy is expected) would need to consent. I think this is Maurice's point, as well. You present your idea in a context that appears good and framed in a protective manner to a child; however, you need to consider all the possible misuses of the technology in different (non-threatening) contexts. That is, the recording when people don't want or expect to be recorded. Importantly, an alert system may be different, because it is not a recording. (Remember, posting your ideas may affect your patent rights, so be careful.) Even if the technology exists, assuming it is able to acquired by you (eg, not someone's protected intellectual property), you might frame your product or service with a branded trademark to distinguish you in the market and give you competitive advantage. Keep thinking and honing -- your intention of trying to protect children with the available and new technologies is good. Remember, view your idea from a challenging variety of misuses and contexts. Even the best ideas are challenged and constantly confronted with destruction. If you could ask Steve Jobs, he would tell you. But, keep trying and honing.
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