Yes you can show multiple images in your popup. The way you do this is your data needs to contain the image you want to display. Here's an example of a CSV file that can be added to a map. It has two attribute fields, called photo1 and photo2 that contain the URL to images.Name,Latitude,Longitude,photo1,photo2
Hospital,34.038344,-117.206536,http://www.esri.com/data/graphics/basemaps1.jpg,http://www.esri.com/data/graphics/imagery4.jpg
Supermarket,34.049054,-117.197436,http://www.esri.com/software/arcgis/arcgisonline/graphics/basemaps/world_imagery.png,http://www.esri.com/software/arcgis/arcgisonline/graphics/basemaps/world_street.jpg
In the Configure Popup option accessed from the layer, you can add images at the bottom. You would add two images and use the photo1 and photo2 fields as the URL (Click the + sign next to the type in field).In this example, the attributes, photo1 and photo2, contain the full URL to the image. Alternatively, if all images were stored at the same location, the field might simply contain the image name, and the rest of the URL could be hard-coded in the URL field when defining the image, like this:http://www.esri.com/graphics/{photo1}Where the value of the attribute for the record would be substituted for the field reference, {photo1}Hope this helps,Mike