perf - Perf is a simple app monitoring solution paired with meaningful alerts.
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.
Treo - Treo is the page speed monitoring tool that helps your customers from obtaining a faster web experience.
UptimeRobot - Free Website Uptime Monitoring
Deppbot - Continuous Updates - Based on your configured schedule, deppbot will run bundle update on your Ruby app and send the result as a Pull Request to GitHub.
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.