I followed the tutorial and put the admob code into a test app and everything seemed to work and I saw the test ads displayed on the screen. I'm not sure why test ads instead of real appeared on the screen, but the code seemed to be working. When I put the admob code into the real app, and created a new admob entry for the real app, I no longer see the test ads. Logcat shows "failed: Ad request successful, but no ad returned due to lack of ad inventory", so I'm not getting any ads on the screen. I'm not sure what I did to disable the test ads, and I'm not sure how to bring them back. Any help would be appreciated.