A Survey of COVID-19 Contact Tracing Apps

TL;DR

This survey reviews COVID-19 contact tracing apps, analyzing their architectures, privacy, security, and user concerns, and discusses future research directions to enhance their effectiveness and adoption.

Contribution

It provides the first comprehensive overview of COVID-19 contact tracing app attributes, deployment examples, and user concerns, guiding future improvements.

Findings

Many apps have been deployed countrywide.

Privacy and security are key concerns for users.

Future research should focus on improving tracing accuracy and user trust.

Abstract

The recent outbreak of COVID-19 has taken the world by surprise, forcing lockdowns and straining public health care systems. COVID-19 is known to be a highly infectious virus, and infected individuals do not initially exhibit symptoms, while some remain asymptomatic. Thus, a non-negligible fraction of the population can, at any given time, be a hidden source of transmissions. In response, many governments have shown great interest in smartphone contact tracing apps that help automate the difficult task of tracing all recent contacts of newly identified infected individuals. However, tracing apps have generated much discussion around their key attributes, including system architecture, data management, privacy, security, proximity estimation, and attack vulnerability. In this article, we provide the first comprehensive review of these much-discussed tracing app attributes. We also present an overview of many proposed tracing app examples, some of which have been deployed countrywide, and discuss the concerns users have reported regarding their usage. We close by outlining potential research directions for next-generation app design, which would facilitate improved tracing and security performance, as well as wide adoption by the population at large.