I have been wanting to post on this for long. There is a very simple way to achieve reflection/epi-illumination microscopy in the new foldscope. For this, I use a simple LED hack that was described by Marie. See https://microcosmos.foldscope.com/?p=13486. This LED unit can now be inserted from the side as seen in this video. The video was made for friends in India and hence the local reference.
One of my favorite pictures is this spider-mite egg that I took with the same hack. This means I can now think about time-lapse photography of spider-mite development.