Mobile First Index Checker - mobile first indexing, mfi, seo, mobile, google
Rank Math SEO - A FREE powerful and lightweight SEO plugin for WordPress
Curatedseotools.com - Curated directory of the best SEO tools.
SEOtooList - Find the best SEO tool for the right job (community curated)
Site Audit by Ahrefs - Cloud based website analysis for 100+ SEO issues
LiveJournal - Online blogging software - free for basic users!