The adoption of COVID-19 Contact Tracing Apps (CTAs) has been proposed as an important measure to contain the spread of COVID-19. Based on a cross-national dataset, this paper analyzes public perceptions towards CTAs and the factors that drive CTA acceptance in China, Germany, and the United States. Public acceptance is highest among Chinese respondents where 60 percent strongly accept the use of CTAs, while in Germany and the United States fewer than 20 percent strongly accept its use. Our study shows that the factors influencing these rates are similar in all three countries. Strong predictors of CTA acceptance are the perceived effectiveness of these apps, previous experience with CTAs and use of other health apps, concerns about privacy, and levels of trust in the state.