Chef knife :: the app
Chef knife mfg :: the app developer
Murder :: stalking
Cooking :: legal tracking
The law prosecutes app developers and makes illegal apps that allow for stalking. :: The law prosecutes chef knife mfgs and makes illegal chef knifes that can be used for murder.
This is not you have stated. Your example world does not map to the real world, as it is a paradox to think a "murdering chef knife" can be discriminated from a "cooking chef knife" when the manufacturer creates it.
And that is the point of the parent commenter. A tracking app can be used for both legal tracking and stalking, but it is absurd to think the developer will know which it is.