It's clear that there are a lot of reservations about privacy. Although governments stress tracing data is exclusively aimed at containment efforts, it's still more than some people are comfortable with. Critics say it's a system that's primed for abuse. Questions have also been raised about how authorities are protecting data, and whether it's enough. In terms of efficacy, some experts have challenged the accuracy of these systems, while some users have complained that their tracing app affects their phone's performance.