As COVID-19 continues to spread, a variety of COVID-19 tracking apps (CTAs) have been introduced to help contain the pandemic. Deployment of this technology poses serious challenges of effectiveness, technological problems and risks to privacy and equity. The "ethical" use of CTAs depends heavily on the protection of voluntariness. Voluntary use of CTAs implies not only the absence of a legal obligation to employ the app but also the absence of more subtle forms of coercion such as enforced exclusion from certain social and work activities. The protection of individual rights to voluntary use can be enhanced through an ethics by design approach in the development of CTAs that treat the introduction of CTAs for what it is: a complete novelty that is being tested for the first time in democracies.