Spying Apps: Good or Bad?

So these spy apps are getting really popular these days. I see this hype everywhere. Workplaces, spouses and even parents getting these for their kids. mSpy is one of the most popular app and being used in workplaces. Read these mSpy reviews to learn more about mSpy and spying apps. I am personally against these apps when they are to be used without consent of the person you are spying on. It's unethical, and illegal too.