Official Wikipedia App for Windows 8.1. Wikipedia is the free encyclopedia containing more than 20 million articles in 280 languages, and is the most comprehensive and widely used reference work humans have ever compiled. Send us your feedback on Twitter @WikimediaMobile. The code is 100% open source and community built. If you are a developer and good at JS/HTML5, then come fork us! https://github.com/wikimedia/apps-win8-wikipedia