hi, i just started using ads a few days ago and had the same problem, the app needs to be realeased and then used for a bit to increase the number of "requests" (a request is made everytime the program tries to access a new ad), once the # of requ...
* to make key
enter this into cmd prompt: cd C:\Program Files\Java\jre1.6.0_01\bin
and then this: keytool -genkey -v -keystore C:\Program Files\Java\jdk1.6.0_23\bin\keystore1.keystore -alias (your name) -keyalg RSA -validity 10000
your app needs to be out for atleast a couple of days and have a few hundred downloads at least before ads show up ALMOST every time... (hint: if you enable "age appropriate" ads you'll usually get more ads showing up)
If you already have an android phone than I wouldn't worry about it because you can test your apps on the emulator to test for different screen sizes, and then use your phone for more accurate testing in terms of performance
if you have NO programming experience what so ever than you should start by learning Java first (get an ebook or find an online webiste that teaches it to beginners or get a physical book on it, I got one last year called "Java: in easy steps" and...