Have you encountered the following error message while importing data?
Shapefile loading error:
Incompatible shapefile data structure
(iGIS does not support 3D data points)
At this stage, iGIS is unable to handle 3D shapefiles correctly, and your shapefiles will need to be edited to remove the z-value.
In the following example, ArcGIS will be used to convert convert 3D shapes to 2D shapes by using the Feature Class to Feature Class tool. It is possible to also use other GIS applications, such as QGIS.
1. To locate the tool most easily, just search for ‘feature class to feature class’. Select the tool that is highlighted in the image below.
2. Select the shapefile that contains the 3D features, and load it into the ‘Input Features’ dropdown box. Enter the ‘save’ location for the new shapefile.
3. Select the ‘Environments…’ button to access the ‘Z Values’ settings. This is where you will disable the z-value of your shapefile to create a 2D shape (see the two images following). Repeat for ‘M Values‘.
4. Click ‘OK’ and you are ready to load your new 2D shapefile into iGIS.
As always, we are happy to assist if you have any concerns or questions regarding this process. Just email firstname.lastname@example.org
— extra info http://forums.arcgis.com/threads/77695-w