Download and save PDF files to your iPhone using the Books app that is part of the iOS operating system. Android devices can also download a PDF for viewing and as a saved file. The way in which you store the PDF is entirely dependent on your preference and the space that is available on your mobile device. For short-term storage, where you store the PDF does not make a big difference, but long-term storage requires a decision between saving the PDF to a cloud storage system or directly to your phone. Either option works well.
The size of the PDF file and the space available on your phone are both important factors in your storage decision. Use your cloud storage for large files that you intend to store for a long time, and use the phone itself for temporary PDF storage, especially when the file size is moderate. Additionally, accessing the file is an important consideration. You need a cellular or Wi-Fi connection to access a file stored in the cloud, while files downloaded directly to the phone are accessible at all times.
Download PDF to iPhone
The most effective means of downloading a PDF to your iPhone is through the Books app that comes on the iPhone. While it's possible to save a PDF using a third-party app, the Apple Books app maintains the PDF's formatting and is designed specifically to store and read PDF documents. Not only does it work for storing and reading PDF files, but you also have the option to add marks to the pages. While it's not a full-fledged editing program, the ability to take notes and mark up documents makes this method interactive, and it functions as a useful tool.
To download a PDF using the Books app, either access the file through an email in the Mail app or a web page using the browser on your iPhone. If needed, use your home computer or laptop to email the file to yourself so you can access it on your phone. Tap the file to open a preview. You can also tap the "Print" icon to generate a preview. Tap and hold the PDF icon in the email and select "Copy to Books" to download the PDF document to the Books app or select "Save to File" to specify whether to save it on your iCloud Drive or on the iPhone.
Advanced PDF Needs
Consider downloading a third-party app for advanced PDF file needs. Outside of basic markings offered through the Books app, no editing abilities are standard for PDF on the iOS operating system. The same applies to Android as well. You can, however, find PDF editing apps through in the App Store when PDF manipulation and customization is necessary.