This App Can Hide Your Phone’s PIN by Using an Optical Illusion

Researchers at New York University’s Tandon School of Engineering have developed an app that could protect your sensitive information and passwords from people looking over your shoulder.

In today’s world where everything is online, users need some kind of insurance about the protection of their data. There are always some awkward eyes looking over for your private information.


While there are a lot of apps which prevent online data theft, the app named “IllusionPIN” helps the user battle against potential spies sitting close to the user.

What this app does is that it generates two different image outputs. The outputs are viewed differently by different users based on the distance from the screen. People looking at a closer distance will see a high-resolution image number pad while people at a distance will see a distorted and reconfigured keypad.

Nasir Memon, a professor at Tandon explained the functionality of app:

The traditional configuration of numbers on a keypad is so familiar that it’s possible for an observer to discern a PIN or access code after several viewings of surveillance video.
Our goal was to increase the resilience of PIN authentication without straining the device or compromising user experience.
On a device running IllusionPIN, the user—who is closest to the device—sees one configuration of numbers, but someone looking from a distance sees a completely different keypad.

This app also reconfigures the keypad button arrangement each time you authenticate or log in from any account on your phone.


The app went through the testing phase where certain simulations were done. The efficiency of the app was tested by replicating the scenarios where people pry over the user’s shoulder.

Two sets of tests were performed. One was performed on phones with IllusionPIN app and one without. All other parameters were kept the same. Tests on 21 participants and a total of 84 attempts of stealing password were made.

Results proved in favor of IllusionPIN. Out of 84 attempts on IllusionPIN phones, none were successful in stealing the password. The result was completely opposite for phones without IllusionPIN app; each attempt of stealing password was successful.

The team further concluded that the app also made stealing passwords extremely difficult using surveillance footage.

The results show that IllusionPIN is a handy app to have if you want to protect your data from shoulder-surfers.

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