Google Analytics & Webmaster Tools are necessary tools for every website owner.
Google Analytics is a free tool that tells you that how many visitors are visiting your site, their sources, most visited pages of your website and many others things.
Webmaster tools(Now, Search Console) is another powerful tool which tells that how your website is performing in search results. You really need this data to optimize your site for search engines.
A single backlink can do wonders in SERPs. So, backlinks are necessary to rank your blog in search engines.
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