What are some alternatives?
When comparing Word Online and LibreOffice - Writer, you can also consider the following products
Apache OpenOffice Writer - Open-source word processor of the Apache OpenOffice suite.
Google Drive - Docs - Create a new document and edit with others at the same time -- from your computer, phone or tablet. Get stuff done with or without an internet connection. Use Docs to edit Word files. Free from Google.
Microsoft Word - Microsoft Word is a commercial word document processor for Windows.
Overleaf - The online platform for scientific writing. Overleaf is free: start writing now with one click. No sign-up required. Great on your iPad.
Notion - Notions big update, now with Evernote import and web clipper
LyX - LyX is a document processor.