Flash tattoos are simple and usually facial tattoos in a pattern that are animated, usually moving to the wearers heart beat.
- Main article: Pretties (book)
Shay gets a snake flash tattoo, and Peris follows with a third eye that blinks to his heart beat. Many of the other Crims also get these tattoos after they broke the floating ice rink with champagne. These all have heart rate triggers, so they can see at a glance how bubbly each other are.
- Main article: Specials (book)
In Specials, the Cutters have huge networks of flash tattoos, covering large areas of their bodies. Shay's face is described as being covered in tattoos and she begs Dr Cable to let her have more. Tally also has them on her hands, and she manages to stop one spinning when she cuts herself before stealing from the Armory. Flash tattoos are part of the Cutters' strange way of life, together with cutting, branding, and hoverboarding.