I just bought an iPad Air 1on Mercari for $25 in mint condition. Handles EPUBs and PDFs like a champ. Battery drains when wifi is turned on. Webkit is horribly out of date, but the kernel says its from 2021? I think webkit was frozen in 2018.
In that era, Safari added new features, including adding support for web standards, in the major update and in a .1 update about 6 months later, Safari 12.1 came out in March 2019.