title: How to promote my own app in my other app using Admob?
body: <p>I have two live apps and like to promote them through each other. I am using Admob for showing ads. After some search I came to know that I can use admob campaign for this purpose.</p>
  <p>I have some Queries regarding this</p>
  <ol>
  <li><p>Did I have to pay google anything to promote my own app in my other app?</p>
  </li>
  <li><p>It's say my ad will only show when I will not get any live ad (ad backfill). So is there any way that after every certain live ads, My ad show? (like after every 10 live ads, my own ad show)</p>
  </li>
  </ol>