Grandstand gives you multiple ways to control what your list and list detail pages look like. Most of this is controlled in the Lists->List Group setup area.
If you run into an issue where images you have uploaded are not showing up in the app it is likely because that specific List Group does not have images turned on. To change this setting go to your specific List Group (Lists->List Group) and change what is selected in the "Location to Show Images" dropdown. The options include:
1. No Images (Default)
2. Full List with Thumbnail Images (example on left above)
3. Detail Page with Full-Width Image (example on right above)
4. Images on Both Full List & Individual Detail Page
Once you have changed and saved your selection be sure to Update your Lists to app.