Long before word broke that MacBook Webcams could be hacked without activating the accompanying light, Josh Luft was a concerned college senior taking a computer programming class. His professor had showed students at Keene State how common  security features in Unix could be worked around. So Luft sought out ways to cover his laptop camera.

“Tape left a nasty residue over the camera, the Post-its fell off after a few days, and everything else I tried was just an eyesore,” Luft explained.

He then designed a plastic clasp — similar to the eyebloc— to cover a camera. But he was discouraged by its failure to fit all of the common gadgets that have cameras. And he wanted a solution for the devices which feature two cameras.

“I started thinking outside the box and realized you don’t need all that material. You just need a proper adhesive,” Luft said.

Luft knew one sticker could cover the camera on any device. He tracked down an adhesive designed for glass and plastic that wouldn’t leave any residue. With that, Luft had camJAMR, a simple solution for people concerned about their cameras being hacked.

Sales started slow, but have taken off recently. While camJAMR is more expensive than a piece of duct tape or Post-it note — a set of 12 stickers costs about $5 — its adhesive is a selling point. When I tested camJAMR it could be removed and firmly reattached to devices without leaving a trace of glue.

There are two advantages that camJAMR offers over eyebloc. It can block the dual cameras that are common on smartphones and tablets. Plus the stickers will fit under a case, and won’t stop a laptop lid from fully closing.