title: Android: How to check if my other apps are installed on a device
body: <p>I have several Android apps in play store and when a user installs one of my apps, how can that app find out that my other apps are installed on this device or not?</p>
  
  <p>I wish to search using : <code>com.developer.*</code>  pattern.
  Can we make such check?</p>