WebGazer is an uptime monitoring platform that checks if your website is up as it should be and notifies you if anything goes wrong
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Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
Backlinks by Neil Patel - A backlinks research tool for competitive intelligence
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
SEMScoop - Find and analyze easy to rank long-tail keywords with free SEMScoop Keyword Difficulty Tool, Start using them for SEO, PPC, content creation and all your marketing activities