I was called to do an inspection after two offices had been repeatedly water damaged due to a roof leak.  Suspected mold growth was found behind the vinyl base cove.  I used clear transparent tape and clear fingernail polish on a microscope slide to prepare the specimens.   Identification to species after digital magnification on an S-5 Samsung phone was made with little difficulty.

The actual Foldscope image  is shown above on the left with the enlarged image of the Chaetomium spp. adjacent.

The actual Foldscope image  is shown above on the left with the enlarged image of the Stachybotrys spp. adjacent.

A full description is available at Roof leak mold evaluation .