UC Browser is a web browser developed by mobile internet company UCWeb, a subsidiary of the Alibaba Group. It was the most popular mobile browser in India and Indonesia, and the second most popular one in China as of 2017. Its world-wide browser share as of May 2022 is 0.86% overall (and 1.48% on smartphones) according to StatCounter. Originally launched in April 2004 as a Java-only application, it is now available on a number of platforms including Android, iOS, BlackBerry OS, Java ME, Symbian, Windows Phone, Microsoft Windows. It has been the subject of several security and privacy controversies, and was banned in India on June 29, 2020, shortly after the 2020–2022 China–India skirmishes started. Functionality UC Browser is a cross-platform web browser primarily targeted at mobile phones. It is known for its small app size and data compression technology, making it popular in emerging markets where people tend to have mobile phones with more limited device memory and internet bandwidth. In particular, the browser is unique in its use of proxy servers, which run data through UCWeb servers before sending it to the user's device, enabling data compression but also posing privacy risks. Additional features of the browser include cloud acceleration, multi-file format downloading, HTML5 web app and cloud syncing features, and "fast download", a feature that downloads files in multiple parts simultaneously. Platforms UC Browser is available as both an Android app and an iOS app, and is also available on several other older or discontinued mobile operating systems including BlackBerry OS, Symbian, and Windows Phone. While primarily a mobile app, UCWeb also offers a Microsoft Windows desktop version (there is no macOS version). Data compression UC Browser uses proxy servers to compress web pages before sending them to users. This process requires less memory on the user's device and lowers data costs; however, it also poses privacy and security risks as all of the data accessed by the user through UC Browser first runs through a UCWeb server, rather than going directly to the user's device. UC+: HTML5, WebApp and add-ons In July 2013, UCWeb announced the UC+ Open Platform. The platform consists of a WebApp store, an add-on platform and an Application Bookmark Platform. It went live with the launch of UC Browser v9.2 for Android. Developers can use a provided SDK to create programs that the browser runs in different scenarios. Users can download and