If you ever experienced difficulties with importing and exporting 3d models between ZBrush, Maya and 3DS Max, you probably would be interested to know about Styx – the script package that, as it developers say, makes faster importing-exporting files between the programs, the creating blendshapes, editing geometries, etc.
The main function of this tool is to save out the active subtool’s active subdiv level to the C:\temp folder. And because every software overwrites the same obj file, communicates through the some “channel”, the communication is not between two programs, rather whatever you want. You can open this obj with other softwares. This way, you can work in Maya, 3DS MAx, ZBrush or uv-editors in the same time by just circling the same geometry through the softwares.