I once developed an ODK form and have them on my Mobile device. However I can't find the .xls file which was used to build the ODK form on my system. Is there anyway of retrieving it back?
The short answer is no. Many years back I think KoboToolbox had experimental support (see Converting the xml form back to xls - urgent - #7 by Patrick_Vinck1), but I dunno if it still exists or works.