A simple way to copy folders or files from your computer to your device is to use free software by Diskaid or iExplorer. These programs are very useful as they can access the files in Atlas and other apps via USB connection to your device.
The example image below shows:

Note: You may need to close Atlas completely (remove it from Apple's "multi-tasking" state by pressing the Home button twice on the device) and re-open before being able to see newly copied files.
The above principles can be applied for copying gpx and kml files to and from Atlas and Solo apps
Please note: Diskaid and iExplorer are third party applications and could therefore be subject to changes outside of our control.