I have followed all instructions and using the latest update 1.1 (released today).
When returning (tapping back) from an ad click from Adduplex everything is ok but when returning (tapping back) from clicking an AdMob ad my app closes and throws a NullReferenceException.
at Google.AdMob.Ads.WindowsPhone7.Support.DownloadHelper.<>c__DisplayClass1.<Run>b__0(IAsyncResult AsyncResult)
at System.Net.Browser.ClientHttpWebRequest.<>c__DisplayClassa.<InvokeGetResponseCallback>b__8(Object state2)
at System.Threading.ThreadPool.WorkItem.WaitCallback_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadPool.WorkItem.doWork(Object o)
I was using AdMob in my app previously with no issues.
I have managed to get my multipage app with adrotator to not throw the above exception by doing the following;
1. Do not use .Dispose at all
2. Put the .Invalidate in the Loaded event
I am not sure what issues will be caused by not calling .Dispose but it is the only way I could stop my app from crashing after returning from an AdMob click.