MarvelScan, the first Tracker-free and marker-free portable 3D laser scanner in the world, is a breakthrough product to change the working method of portable 3D laser scanner with faster scanning efficiency. Thanks to the unique Inside-Out monocular positioning technology, during the whole scanning procedure, operator does not need to place sticker markers at all. Compared to other optical tracking scanning system, MarvelScan does not require the rigid structure with markers around scanner or an optical tracker at all, which improves portability and simplify the calibration procedure dramatically.