Die Next — Jonathan Stone

Read this "high-octane thriller" that "calls to mind...Jeffery Deaver and Alfred Hitchcock" and questions everything that you have ever saved on your phone (Mystery Scene Magazine).
In a crowded coffee shop, Zack Yellin swaps identical-looking cell phones with the businessman next to him. It's an honest mistake-and a deadly one. Because the "businessman" is actually a professional-and highly volatile-hit man named Joey Richter, and his phone is filled with bombshell evidence.
If Zack takes Joey's phone to the police, will they believe his swapped cell phone story? Would they even be able to protect him? Because the hit man now has Zack's phone with the phone numbers and addresses of Zack's new girlfriend Emily, his best friend Steve, and all the texts and information from Zack's life.

Whether Zack keeps the phone or ditches it, Joey will kill him for what he now knows. In cat-and-mouse twists, turns, and continually mounting terror, one thing is clear: Zack is next on the hit man's list.