Trying to figure out directory structure bt-200

Hello I am trying to figure out how to write to file using the bt-200. I am using unity and c# to try and write an application for the glasses and I need to create and write to a txt file. I am using the line System.IO.File.WriteAllText (@"file.txt", data); to attempt this. What I cannot find is the proper path to use since I am unfamiliar with the devices directory structure. I have also tried to use path = System.IO.Directory.GetCurrentDirectory(); but this has not worked either and I cannot find the file I have supposedly generated. Any help would be appreciated.