This app allows you to share the web page you are reading in your browser or RSS feed reader to any app such as twitter or facebook. It will create a friendly shared message containing the shortened URL using x90.es and the page title.
On your browser press Menu -> More -> Share page -> Share With x90.es
It will create the short URL using x90.es, and fetch the page title. Once done, you'll be displayed the "Share" options again, where you can send the short URL with page title message to any other application.