Overleaf - The online platform for scientific writing. Overleaf is free: start writing now with one click. No sign-up required. Great on your iPad.
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.
TeXstudio - TeXstudio is an integrated environment for writing LaTeX documents.
Wondershare PDFelement - All-in-one PDF editor
LyX - LyX is a document processor.
Foxit Reader - Foxit Reader is a free and light-weight multi-platform PDF document viewer.