Rich Internet Application (RIA)
RIAs used to depend on browser plugins such as Flash and Silverlight. Since plugins are being abandoned (Chrome has stopped supporting them, even Microsoft's new browser Edge does not support its own plugin - Silverlight), old RIAs need to migrate to a new model - HTML/JavaScritp. One approach for Silverlight apps is using Knockout.
Mobilize.net used to promise a migration tool for Silverlight to HTML5, but apparently they have canceled the plan based on an email from their Technical Product Manager.