Apps similar to Havok Physics include Bullet Physics, which is free and open source. Other options are Jolt Physics and Open Dynamics Engine. In total there are three apps like Havok Physics for Mac, Windows, Linux, Android and iPhone.
Bullet Physics SDK: real-time collision detection and multi-physics simulation for VR, games, visual effects, robotics, machine learning etc.
A multi core friendly rigid body physics and collision detection library. Written in C++. Suitable for games and VR applications. Used by Horizon Forbidden West.
Netherlands
EU
ODE is an open source, high performance library for simulating rigid body dynamics. It is fully featured, stable, mature and platform independent with an easy to use C/C++ API. It has advanced joint types and integrated collision detection with friction.
