They are not necessarily watching or listening to you, but they could be watching your screen.
Some people are worried that some Android apps could be listening and watching them. That is very unlikely, however. But according to this year-long study, some apps may have been secretly recording your screen. A study was done on 17,260 apps, and it turns out that a few of them have been secretly recording users’ activity and sending that data “to places”, to be used for advertising.
However, the testing concluded that none of the apps tried to access the microphone of the camera. Instead, the testing program noted that multiple apps would share screen recordings with third parties. With that said, it’s also important to realize the limitations of the testing software. The software was set up to monitor files sent by apps, and did not possess the capabilities to create user accounts and passwords — essentially limiting the portions of an app it could test.