If users view your API maps using Safari on an iPad in landscape mode then the bottom of your map (including the map scale) likely is not on the iPad screen. In other words, the rendered map is too tall when the iPad is in landscape mode.
Since this happens to the 'example' maps that Google has posted, this problem is widespread.
I know it happens on iPads using iOS 7.1.2
I do not know if it happens with earlier versions of iOS.
If you are concerned by this, please 'star' the bug report I filed:
http://code.google.com/p/gmaps-api-issues/issues/detail?id=6990