title: How to create an android app that activates on shake events when screen locked?
body: <p>I want to create an app that **starts the Main activity whenever the device shakes, even when screen locked. Can anyone explain how to do that? </p>
  
  <p>I have an idea that it requires to create a service that runs in background, but I am struggling with actual coding and don't know how to do it.</p>