Monitor Backlinks - Easy Link Management - SEO Tool for automatically checking your backlinks.
Watchtower - "Watchtower monitors your competition's websites and alerts you to important changes instantly."
Topvisor - All in one SEO and PPC tools for better marketing.
LaunchKit - Open Source - A popular suite of developer tools, now 100% open source.
Botify - Traffic Managers, SEO Managers, Webmasters:Crawl your site to extract all of its metadata and identify areas for improvement
Material Design for Bootstrap 4 - Powerful and free UI KIT for the newest Bootstrap 4 and Material Design