Polaroid has this cool new smartphone printer that is basically a projector in a box that projects your photo from your smartphone on to traditional Polaroid instant film.
As soon as I saw it, I thought, wait, didn't I use an iPhone to make a picture once? After a bit of digging, I found my Flickr album of when I used an iPhone and an old camera as an enlarger back when we lived at our old apartment.
I would insert an image here, but I disabled downloading of images on my own Flickr and can't find it on my computer, so go to Flickr to see what I did. Basically, put the camera lens down, place film negative on the back of the camera, place custom light box (with appropriate contrast filter!) atop of the camera and film, etc. It was the original iPhone. And I only used it as a light source. The exposure time on the paper was over 10 minutes, due to reciprocity failure.
Anyway, thinking of that then reminded me of making contact prints with a monitor and photo paper, another wholly unpractical method of making photos.