One reason is that Send to Kindle is a service that allows you to send documents to your Kindle library on your Kindle devices and Kindle app at no additional cost. File Upload. Go back to the PDF, hold your cursor, drag the document from its location, and drop it into the Kindle document folder Drag and drop the PDF file from the original location to the Kindle documents folder. Sign in. By using Send to Kindle, you agree to the terms here. Sign in to send files to your Kindle library Or to sp