WebGazer is an uptime monitoring platform that checks if your website is up as it should be and notifies you if anything goes wrong
UptimeRobot - Free Website Uptime Monitoring
Website Grader - Grade your website's strengths and weaknesses in seconds.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Smaller - Make your websites load faster
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.
Textalyzer - Analyze text readability and SEO parameters