Blisk
Free
Blisk is a browser for web developers. Blisk is a toolbox for development, debugging and testing: emulation, sync, analytics, and screenshots.
Sauce Labs
Commercial
Sauce Labs provides the world's largest cloud-based platform for the automated testing of web and mobile applications.
Browsershots
Open Source
Browsershots is a system for capturing screenshots of Web pages in many different browsers.
Compare BrowserStack with alternatives
Compare Browsershots and BrowserStack and decide which is most suitable for you.
Compare Sauce Labs and BrowserStack and decide which is most suitable for you.