BrowserStack is a cloud-based cross-browser testing tool that allows developers to test their websites and mobile applications on various browsers and devices. The company was founded in 2011 by Ritesh Arora and Nakul Aggarwal, and is headquartered in Mumbai, India. BrowserStack has over 2 million registered users and is used by companies such as Microsoft, Airbnb, and Twitter. The company has raised $50 million in funding to date, and has offices in San Francisco, Dublin, and London.