dropbox-upload-version1-blog.m

//Assuming already existing "@property (nonatomic) Dropbox* dropbox;"(DropBox,Box,,GoogleDrive,OneDrive...)
UIImage * image = imageSource;
NSData * pngImageData = UIImagePNGRepresentation(image); // loading data from some source. (PNG)
NSInputStream * inputStream = [NSInputStream inputStreamWithData:pngImageData];
[self.service uploadFileToPath:@"/mudkip.jpg" withStream:inputStream size:imageData.length overwrite:YES];