Research depth
Discovery
How well the tool supports keyword, competitor, SERP, backlink, or market research before execution.
cognitiveSEO
Broad first-party SEO research coverage across links, rankings, keywords, competitors and site issues.
The homepage lists Site Explorer, Keyword Tool, competitor strategy research, backlink analysis, rank tracking and a comprehensive Site Audit: https://cognitiveseo.com/
Screpy
Covers keyword research, SERP analysis, organic keywords, competitor ads, backlinks, referring domains, and Search Console, but depth and quotas vary by plan.
Feature directory lists Keyword Research, SERP Analysis, Organic Keywords, Competitor Ads, Backlink Checker, Referring Domains, and Search Console: https://screpy.com/features/