Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
No, Android runs apps in a sandbox, meaning they cannot affect other running apps. As such, your app cannot prevent another app from running.
Well why have it if not protected with all apps.
There are already apps that let you require a password to launch other (specified) apps.
What do you mean by "control"? Interfering with the operation of another running app is not only difficult (because of the sandboxing), and would certainly require root, but also violates the Play Store rules.
i am just developing an app for parents to control child mobile.Still not understanding what you want to do.