Wikipedia

The official Wikipedia Android app is designed to help you find, discover, and explore knowledge on Wikipedia. Settle a bet with a friend by doing a quick search for a specific article, or dive into featured articles, images, recommendations, and more using the Explore feed. With more than 40 million articles in nearly 300 languages, your favorite free online encyclopedia is now more useful than ever.

Features:
Explore feed: Recommended Wikipedia content including current events, popular articles, events on this day in history, suggested articles based on what you’ve already read, and more. The feed is fully customizable — select the types of content you want to see, or rearrange the order in which different types of content appear.

Multilingual support: See Explore feed content in multiple languages, easily switch between languages while searching for articles, and read articles in any of the nearly 300 Wikipedia-supported languages. Customize which types of Explore feed content you see in each language, and which language appears first in search.

Reading lists with offline access: Save and organize the articles you browse into reading lists, which you can access even when you're offline. Create as many lists as you like, give them custom names and descriptions, and populate them with articles from any language wiki. You can also sync lists to your Wikipedia account across devices.

Color themes: With a choice of Light, Dark, and Black themes, as well as text size adjustment, you can customize the app for the most comfortable reading experience.

Voice-integrated search: Easily find what you’re looking for with a prominent search bar at the top of the app, including voice-enabled search on your device.

Nearby: Learn more about what’s around you by selecting points on an interactive map to see articles related to your current location.

Link previews and article tabs: Tap on an article to preview it without losing your place in what you’re currently reading. Or press and hold a link to open it in a new tab so you can keep reading the current article, and switch to the new tab when you're ready.

Image gallery: Tap on an image to view the image full-screen in high resolution, with options to swipe for browsing additional images.

Definitions from Wiktionary: Tap-and-hold to highlight a word, then tap the "Define" button to see a definition of the word from Wiktionary.

To send your feedback from the app:
In the menu, press "Settings", then "About the Wikipedia app", then "Send app feedback".

The code is 100% open source. If you have experience with Java and the Android SDK, then we look forward to your contributions!
https://mediawiki.org/wiki/Wikimedia_Apps/Team/Android/App_hacking

By using this app, you agree to the automatic transmission of crash reports to a third-party service provider. If you would like to disable this feature, press "Settings," then turn off "Send crash reports" under the Privacy section.

Explanation of permissions needed by the app: https://mediawiki.org/wiki/Wikimedia_Apps/Android_FAQ#Security_and_Permissions

Privacy policy: https://m.wikimediafoundation.org/wiki/Privacy_policy

Crash report third-party service provider’s privacy policy: https://privacy.microsoft.com/en-us/privacystatement

Terms of Use: https://m.wikimediafoundation.org/wiki/Terms_of_Use

About the Wikimedia Foundation:
The Wikimedia Foundation is a nonprofit organization that supports and operates Wikipedia and the other Wikimedia projects. The Wikimedia Foundation is a charitable organization funded mainly through donations. For more information, please visit our website: https://wikimediafoundation.org/wiki/Home