The quick start guide for the Aquarius M10 Ubuntu Edition provides a web address on www.bq.com for downloading the full user manual for the M10. Although manuals for other Aquarius devices exist, there is no manual for the M10 on this web page. Is there some other way to download the user manual?
Go to bq.com and click Support >> Downloads >> Tablets >> Aquaris M10 Ubuntu Edition. Then choose your preferred language in the select box provided and there you go. I found the full manual here:
Hope, that helps.