1st Case by James Patterson

Angela

Hoot's government career begins with an ending. Her unorthodox

programming skills get her kicked out of MIT's graduate school and into

the Bureau's cyber-forensics unit.

A messaging app with

sophisticated tracking capabilities surfaces. Its beta users, all young

women, are only identified as they turn up dead in their bedrooms. As

Angela races to crack the killer's digital code, their technical rivalry

escalates. She must deny the killer access to her personal life, or

risk losing her life to the underbelly of the Internet.