MuPDF - MuPDF is a lightweight PDF and XPS viewer.
Foxit Reader - Foxit Reader is a free and light-weight multi-platform PDF document viewer.
Okular - Okular is a universal document viewer based developed by KDE.
Document Viewer - Document Viewer is a highly customizable document viewer for Android. - SufficientlySecure/document-viewer
Adobe Acrobat DC - Make your job easier with Adobe Acrobat DC, the trusted PDF creator. Use Acrobat to convert, edit and sign PDF files at your desk or on the go.
Evince - Evince is a document viewer for multiple document formats: PDF, Postscript, djvu, tiff, dvi, XPS...