For now the best is to divide the scene in multiple objects so that they can be detected out of the screen,
the engine is Maratis one, called MEngine (itself using Maratis core MCore), it is a virtual engine, it uses OpenGL on desktop and openGLES on phones (iOS). It could theoretically uses other things like directx, console systems or software engines.
Games are coded in lua script or/and c++ pluign (using the engine functionalities)
If you really need LOD, you can always do a little c++ code that hide/show different parts of a mesh (called subMesh) according to the camera distance. There is a decimate modifier in Blender that can be used to generate manually multiple LOD models.