How to force Admob to refresh on Android

As an alternative you can also have Admob refresh ads for you at time intervals you specify. In Admob go to "Sites and Apps", then click "Manage Settings" for the app you want. Then click on "app settings". There under "Automatic refresh" you can change the refresh rate for ads in your app.

EDIT: with the new admob interface it is under Monetize > My App Name > My Add Unit Name > Refresh Rate (thanks ripegooseberry)

With the new SDK now it is:

AdView.loadAd(new AdRequest());

Old API version:

AdView.requestFreshAd();

New API version:

AdView.loadAd(new AdRequest());

Also, you can simply set a refresh interval with the refreshInterval attribute on the AdView element in your layout XML file. Or you can set the refresh interval for the ads in your app via your account settings on the AdMob website.

Documentation: http://code.google.com/mobile/ads/docs/android/intermediate.html#adrefresh