CAD Assistant

There are many free CAD viewers apps for Android.

 

Only a few of them can open almost every file format of 3D models.

 

Just a couple of them offers a realtime rendering with more than one light source direction.

 

And then,there is an app called CAD Assistant. I would not call it a king of Android CAD viewers, because this app is their GOD.

 

CAD Assistant
Price: Free