Zoho has enabled drag and drop functionality for sales orders and purchase orders in Zoho Books.  Currently this functionality is not enabled for Purchase Receives, which require you to "upload your files" via the file manager rather than simply dragging the file onto the page.  

Not sure on the rational of having different file upload methods for different screens, perhaps Zoho has a reason but my 'idea' (not sure if it's brilliant) is to enable drag and drop uploads of files for Purchase Receives.

If I'm missing anything, feel free to let me know, otherwise Zoho team it would be good if you can consider improving the 'consistency' with the UI experience so it's the same process for all screens (i.e. some screens can accept a drag-and drop file, others require you to manually go find the file in the OS file manager).