How to create your PDF reader Android App?

https://programmerworld.co/android/how-to-create-your-pdf-reader-android-app-complete-source-code/

https://github.com/MindorksOpenSource/Open-PDF-File-Android-Example

https://github.com/barteksc/AndroidPdfViewer/tree/master/android-pdf-viewer/src/main/java/com/github/barteksc/pdfviewer