If you are looking to create or view PDFs on IOS in Delphi XE8 Firemonkey the DPF IOS libraries really make it easy. This example (based on the DPF IOS demo) shows how to create a PDF on the fly, view the PDF, and open the PDF in third party apps on IOS like PDF Expert and Google Chrome. Creating the PDF is handled by a function called CreatePDFfromView(). The PDF viewer is handled by the TDPFQLPreviewController component. And finally opening the PDF in a third party app is handled by the UIDocumentInteractionController component. The UIDocumentInteractionController component is part of the FMX RTL which means you can use it in normal FMX apps as well. DPF IOS is used for the PDF viewer which means you can not mix other FMX controls on the same form with the PDF viewer. For a normal FMX app you can just use TWebBrowser to view PDFs under IOS which makes DPF IOS not a requirement. Obviously this example is only for IOS and not for Android, OSX, or Windows. You should be able to use the example with Appmethod as well. Full source code is provided. Here is a code snippet from the example:
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