Using a 3G iPad in the field, even with good cellular service, it is difficult to click on a marker without the selection screen closing immediately. The mapping works fine, sometimes there is a delay depending on resolution, then the markers appear. Sometimes it takes a tap, sometimes a double tap to open the screen that identifies the monument and gives you the option of what associated content you wish to view. At home on Wi Fi there are no issues whatsoever. Excellent product!!!!!!!!