Okay so I found the solution.
Google guide iOS developers on how to implement AdMob SDK, however they are missing some info. They tell you it's mandatory to add these Frameworks:
- AudioToolbox.Framework
- MessageUI.Framework
- SystemConfiguration.Framework
- CoreGraphics.Framework
To solve the error I added this ones also:
-CoreData.Framework
-AdSupport.Framework
-CoreTelephony.Framework