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.
BackHub - Backup and archive your GitHub repositories with BackHub. Find us on the GitHub Marketplace.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Cloudback.it - Cloudback secures your GitHub repositories with recurrent data backup. With Cloudback you can use your favorite cloud storage provider or a built-in one.
Better Uptime - We call you when your website goes down
GitProtect.io - Fully manageable, most professional GitHub and Bitbucket backup