It is not $500 it is $200 and does your free "SafeBox" app also have a separate "brain box" that will connect with your app to nullify any outside information to given to third party individuals?
Personally I do not mind paying a extra $180 to know no info from my kids cell phones are not transferred to molesters or pedophiles. I also know in this area of "generic equivalency" some step parents could care less... not all but as stated some. I deal with them daily.
Good luck on your self made app but I would check all new numbers daily and have no financial info on it. If not you are welcoming all public "looney's," and I do not mean the cartoon ones.