SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
Optmyzr - Optmyzr AdWords Tools. Optimization Solutions, Quality Score Tracker, Landing Page Checker, and more. Free Trial Available.
Lumar - (Previously DeepCrawl) Hosted SEO spider to analyze and find problems with websites.
Freshmarketer - An all-in-one CRO suite.
Website Checker Tech - WebsiteChecker.Tech is SaaS tool that detects SEO and availability issues of your website, making it easier for you to fix them.
Crazy Egg - Through Crazy Egg's heat map and scroll map reports you can get an understanding of how your visitors engage with your website so you can boost your conversion rates.