SumatraPDF
6.3#8 in file viewer softwareFree planFree planWindows
VisitSumatraPDF suits Windows users who want a free reader for documents, ebooks, or comics, including readers who need text-to-speech or keyboard-only use. Its portable version may suit people who want to run it without installation.
ViewAnyFile.app suits people who want to view or convert varied file types in a browser, including on phones, tablets, or desktops. Clinical users should note its stated HIPAA certification limitation.