Sumatra PDF - Sumatra PDF is a slim PDF/DjVu/EPUB/XPS/CHM/CBR/CBZ/MOBI viewer for Windows.
Apprentice Alf's DeDRM Tools - Everything you ever wanted to know about DRM and ebooks, but were afraid to ask.
Foxit Reader - Foxit Reader is a free and light-weight multi-platform PDF document viewer.
AppleMacSoft DRM Converter for Mac - Legal Convert iTunes and Apple Music M4P to MP3 on Mac with DRM Converter 3.
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.
Sidify Music Converter - Sidify Music Converter for Spotify is a popular tool used to convert Spotify music to MP3/AAC/WAV/FLAC/AIFF/ALAC. It keeps original audio quality and ID3 tags after conversion.