To spy on someone’s cell phone for free depends on what exactly one wishes to know:
- Where another person is;
- How they interact with others;
- What they are doing on the Internet;
Respectively, different services can meet these needs. For example, to find out the phone’s location, Google’s Find My Phone comes in handy. To read Verizon phone’s messages, one may use its program Smart Family which allows reading other members’ ones. Both options are relatively free of charge.
But to get more private information, spyware is the only solution. The application is paid.