LibreOffice is very good considering that it doesn’t cost a kopek to the end user.
Donations to the project are entirely voluntary, and in some cases, tax deductible. It is available for free from the LibreOffice website download page.
If you want to install LibreOffice on macOS via the Apple Store, a company called Collabora offer both LibreOffice Vanilla for a paltry amount with regular updates, or alternatively, their own branded “enterprise ready” version for a slightly higher cost, called Collabora Office. Whether or not these commercial versions can be truly considered to be “enterprise ready” is up for debate. They don’t include any Java support for example, which is a fairly significant limitation if you are interested in using databases for creating reports, or using any of the many Java-based extensions that can be installed separately for LibreOffice.
There is even a version for iOS. I honestly don’t know how capable the iOS version is, as I don’t have an iPad or iPhone.
@Nigel-at-BUF-House originally indicated that he was looking at an Android solution. There is a version of LibreOffice for Android, which is currently made available by Collabora through the Google Play store. Obviously, it is not identical to the LibreOffice that one can install on Win/Lin/Mac, and has a more limited range of functionality compared to the full blown PC/Mac versions .
Full Disclosure : I do not work for any of the above-mentioned companies, but I am one of many volunteers in the LibreOffice project, my particular areas of interest being in bug hunting/triaging and database usage.