Crawly is a tool that crawls your web applications to find out broken pages to help you to maintain it. Crawly has a powerful alerting system that if any page of your project is broken, you will get a notification. Crawly also offers you to monitor your all pages of your application in historically.
Crawly cheapest service which is combining all monitoring services in a rich, reliable and modern dashboard. It does not only monitor your homepage but the entire application from 20 different regions.