LibreOffice - Free office suite, open source, and compatible with .doc, .docx, .xls, .xlsx, .ppt, .pptx files. Updated regularly – download for free. Originally based on OpenOffice.org.
TeXstudio - TeXstudio is an integrated environment for writing LaTeX documents.
WPS Office - Would you need Office Word, Excel or PowerPoint for Home, business or School? WPS.com would give you right version for you.
Overleaf - The online platform for scientific writing. Overleaf is free: start writing now with one click. No sign-up required. Great on your iPad.
Asana - Asana project management is an effort to re-imagine how we work together, through modern productivity software. Fast and versatile, Asana helps individuals and groups get more done.
LyX - LyX is a document processor.