A no-phone/no-app contact tracing hardware token

TL;DR

This paper presents an open-source, hardware-based contact tracing device that uses Bluetooth Low Energy on an ESP32 micro-controller, offering a privacy-preserving alternative to mobile app-based contact tracing.

Contribution

It introduces a low-cost, easy-to-assemble contact tracer hardware that operates without a mobile phone or app, enhancing privacy and accessibility.

Findings

Device costs less than $20USD

Can be assembled and configured within minutes

Operates effectively using Bluetooth Low Energy

Abstract

We report the development of an open-source, hardware-based contact tracer, made from readily available parts, costing less than $20USD. This work was motivated by the need for a technology-assisted contact tracer that avoids privacy issues found with those involving a mobile phone. Contact tracing is done here without the use of a mobile phone or an app at all. Instead, contact tracing is implemented using Bluetooth Low Energy on an ESP32 micro-controller. The ESP32 is used to both advertise and receive health information to others in close proximity, forming a strictly peer-to-peer contact tracer. The contact tracer can be assembled by an individual and configured use within minutes.