PDFKit Page Rendering

There are millions of apps on the App Store and they share a lot of things in common, so Apple includes packages of shared code in iOS called Frameworks that let developers reuse features and components. Apple creates and maintains the code (making sure it’s secure and provides a consistent experience) so developers can adopt new features quickly and reliably.

PDFKit is the name of Apple’s framework for working with PDF files. It was introduced for the Mac all the way back in 2004, but it wasn’t until late last year with iOS 11 that they brought it to the iPhone and iPad. It helps apps display, search, and even edit PDF files in a variety of different ways. It reduces the amount of code we have to maintain and gives us instant access to functions we haven’t yet been able to write on our own.

It can also display pages and embedded annotations, which is something we’ve offered for some time now, but PDFKit was written by a much larger team and is constantly being updated and improved. Apple’s implementation is broader and produces results more like what you’d see in their other apps (on both iOS and macOS).

With forScore 10.3.5 we added the ability to use this new rendering code to display pages and thumbnails, but we disabled it by default until we knew for sure that there no unforeseen issues. We’ll be enabling it for all users with a future update, but you can see the difference for yourself by turning it on in forScore’s settings panel. It only affects the way pages are displayed within forScore, so if you don’t like it you can always turn it off again without any negative side effects.

If you don’t see any issues, leave it on! Apple’s engineers have put a lot of work into making PDFKit, and they know a lot more about how iOS is built than we possibly can.