What SEO Tools are useful to use?
Google PageSpeed Insights.
Google Analytics.
Google Webmaster Tools + Bing Webmaster Tools.
Google keyword planner
Google analytics tool
Google webmaster tool
Google Adwords
Ahrefs
Copyscape
Search Engine Spider Simulator
Keywords Suggestion Tool
Domain Authority Checker
Google webmaster tools, google analytics and alexa etc are good tools to be used.
Webmaster tool
Google analytics
Alexa
SEMrush
Rank signal