V-REP is described as 'is the Swiss army knife among robot simulators: you won't find a simulator with more functions, features, or more elaborate APIs'. There are three alternatives to V-REP for Linux, Windows and Mac. The best alternative is Gazebo Robot Simulator, which is both free and Open Source. Other great apps like V-REP are Webots (Freemium, Open Source) and Marilou Robotics Studio (Free Personal).
Webots is a development environment used to model, program and simulate mobile robots. With Webots the user can design complex robotic setups, with one or several, similar or different robots, in a shared environment.
Marilou Robotics Studio is a modeling and simulation environment for mobile robots, humanoids, articulated arms and parallels robots operating in real-world conditions that respect the laws of physics.