It's bad to track people's movements without their consent.
Carrie is afraid that her boyfriend will cheat on her.
Carrie wants peace of mind.
Carrie decides that it's better to not just assume her boyfriend will cheat.
Carrie installs an app on her boyfriend's phone to track where he is 24/7.
Carrie calms down and is able to enjoy the relationship.
Carrie follows her boyfriend on the maps excessively and has no time for anything else.