Dropbox - Online Sync and File Sharing
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.
Box - Box offers secure content management and collaboration for individuals, teams and businesses, enabling secure file sharing and access to your files online.
Microsoft 365 - Boost your productivity with reliable access anywhere with services like email, calendar, file sharing, meetings, instant messaging, and Office Online
WeTransfer - WeTransfer is a free service to send big or small files from A to B.
ONLYOFFICE - ONLYOFFICE is a complete office and productivity suite.