The Proxy & User-Agent Switcher is a Chrome extension developed by D09r. It is a free add-on that falls under the category of Browsers, specifically Add-ons & Tools. This extension is designed to help users with geolocation-testing and mobile device-testing of any websites.

With the Proxy & User-Agent Switcher, users can easily switch between different proxies for geolocation-testing purposes. This feature allows them to test how a website behaves in different locations around the world. Additionally, the extension offers a user-agent switcher, which enables users to simulate browsing from different mobile devices. This is particularly useful for testing the mobile responsiveness of websites.

Other notable features of the Proxy & User-Agent Switcher include the ability to import and export custom proxy profiles, automatic turn-off of the proxy to keep usage under control, and the option to auto-reload the current page using a selected proxy or user-agent. The extension also supports automatic synchronization of the proxy configuration via the user's Chrome account.

Overall, the Proxy & User-Agent Switcher extension is a valuable tool for developers and testers who need to perform geolocation and mobile device testing on websites. Its user-friendly interface and range of features make it a convenient choice for those in need of such functionality.