istoppers

istoppers are a type of security device designed to prevent unauthorized access to electronic devices, primarily smartphones. They function by physically blocking the charging port of a device, thereby preventing data transfer or charging via a USB connection. This is achieved by inserting a small, often plastic or metal, component into the port that is designed to prevent a standard USB cable from making a full connection.

The primary use case for istoppers is to protect against juice jacking, a malicious practice where public USB charging stations are compromised to steal data from connected devices or install malware. By inserting an istopper, a user can still charge their device from a public port, but the data pins on the USB connection are disabled. This ensures that only power can flow, leaving the device's data vulnerable.

istoppers are typically small and portable, making them easy to carry on a keychain or in a wallet. They are a passive security measure, meaning they do not require software installation or active management. While effective against basic juice jacking attempts, they do not protect against other forms of data theft or malware. The effectiveness of an istopper depends on its design and how securely it obstructs the data pins of the USB port. Some are designed to be universally compatible with standard USB-A ports, while others may be specific to certain port types like USB-C.