Governments and businesses worldwide are creating smartphone apps to help track the spread of COVID-19. Tracking the spread of a disease is an important step in stopping its outbreak（爆发）. By tracking down people who have been in contact with COVID-19 patients, health researchers can warn them, and keep COVID-19 from spreading further. This is called contact tracing（接触者追踪）. As governments remove COVID-19 limits, they’ll need to be able to quickly find and control new outbreaks. Contact tracing will be an important part of the process. But because COVID-19 spreads so quickly to so many people, it’s almost impossible to trace all contacts with phone calls. That’s why many people hope that digital contact tracing with smartphones will help. Most contact tracing apps collect information about where people have gone and the people they’ve had contact with. The apps can tell users when one of their recent contacts has been found to have COVID-19. Some systems also tell governments or health care workers. Now many apps have been developed all over the world . But some people worry the apps are being made too quickly and may not protect people’s private information. What do you think of this kind of app?