Cachet - Cachet is a free, open source status page for your API, service or company. Built with all of the features that you'd expect from a status page.
StatusNotify - StatusNotify monitors the status of 250+ cloud services.
cState - 🔥 Free & open source under MIT!
IsDown App - Monitor all your cloud services status pages in one place
Status.io - Status.io is a platform for system status pages and status notifications. Companies rely on Status.io to track outages, schedule planned maintenances, broadcast status notifications, and much more; and their customers love the transparency.
DownDetector - A simple service to tell you whether a website is down.