StatusNotify - StatusNotify monitors the status of 250+ cloud services.
Indatus - Indatus – A Creative Editor Making Your Photos Gorgeous an all-in-one photo-editing application developed by Thang Dinh.
IsDown App - Monitor all your cloud services status pages in one place
ClearStatus - Create your professional status page in minutes, free.
DownDetector - A simple service to tell you whether a website is down.
StatusGator - Monitor all your hosted applications, vendors, and websites, and keep your team informed of outages. StatusGator is the world's premier status aggregator, status page, and website monitoring tool.