Arkio models are exported by opening the model carousel from the Utilities menu at the bottom of the main menu and selecting the export option. An obj and mtl file are created in the Arkio exports folder in your local documents directory.
Only solid shapes and custom imports get exported with their material setting and texture files. These can serve as an underlay/reference model to load in other applications. The OBJ file format is supported by Rhinoceros and 3DsMax and can be converted to other formats using those applications or plugins for other modeling apps.
There are currently no settings for the export format and the models get exported in the metric system (1 unit = 1 meter). We would love to know what 3D format you would like to see next.