Question: how to transfer pdf file to iphone from windows without itunes?
Answer: The three solutions are:
Connect your iPad (running iOS 8 and later) to your computer (Mac/PC), and run EaseUS MobiMover. ... 
Click the "Add Contents" option to copy books from the computer to your iPad. ... 
Then a new window will appear, in which you need to select the PDF files you want to copy to your iPad.