thanks barx and cableguy!
I suspect you're right, only one activity can be on the display once. Some weeks ago I got the admob working right, but unfortunately it took the keyboard focus. Result was that once I pushed a key in order to play the game, I triggered the admob. This would be good for my admob business, but would drive users crazy...
Then Erel gave some advice of setting the focus correctly and that >>nearly<< worked.
http://www.b4x.com/forum/basic4android-updates-questions/9323-admob-takes-keys-focus.html Idea was to have two views. The first one is the adview and the second is the game. Problem was not quite solved. I got impression that the setting the focus of input is a wee bit tricky.
It would be ok, if only the tap on the adview would trigger the admob. This I haven't achieved yet... Well, back to drawing board, thanks for replies!
Kapslok