Modified Calculators: Hidden Screens & Text Storage

1. Overview

Modified calculators are exam cheating devices designed to look identical to approved scientific calculators while containing hidden functionality — most commonly a secondary LCD screen capable of displaying pre-loaded text files, images, and notes.

These devices occupy a unique position because calculators are one of the few electronic devices routinely permitted in exam rooms.

2. How Modified Calculators Work

A typical modified calculator contains two display systems:

• Primary display — a standard calculator LCD that functions normally.
• Secondary display — a hidden LCD or OLED screen that shows pre-loaded content.

Switching between displays takes approximately 300-500 milliseconds.

Advanced Models: Live Chat Calculators

The most expensive modified calculators ($200+) integrate WiFi connectivity and a miniaturized camera.

3. Types of Modified Calculators

4. Calculator Bans and Approved Lists

• College Board (SAT/AP) — maintains a specific list of approved calculators.
• University exam policies — increasingly require university-provided calculators.
• Professional certification exams — CPA, CFA, and medical board exams restrict to approved models.

5. Detection

Modified calculators are primarily detected through physical inspection:

• USB port location — modified versions often have ports in different positions.
• Weight difference — additional electronics make them slightly heavier.
• Memory check — proctors can reset calculator memory.
• Model verification — comparing against an approved model database.