Workflow
Make it in Laser Graffiti, then take image into FileOnTap. Matched from what each app's own site says it takes in and gives out.
Step 1
Draw on walls by pointing a laser at a projector-webcam setup.
Step 2
Takes image from Laser Graffiti. Free online / browser File Converter — local, no upload.
More about Laser Graffiti · Ask Vibed Guide for a longer workflow