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README.md

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 Kotatsu is a free and open-source manga reader for Android with built-in online content sources.
 
-[![Sources count](https://img.shields.io/badge/dynamic/yaml?url=https%3A%2F%2Fraw.githubusercontent.com%2FKotatsuApp%2Fkotatsu-parsers%2Frefs%2Fheads%2Fmaster%2F.github%2Fsummary.yaml&query=total&label=manga%20sources&color=%23E9321C)](https://github.com/KotatsuApp/kotatsu-parsers) ![Android 5.0](https://img.shields.io/badge/android-5.0+-brightgreen) [![weblate](https://hosted.weblate.org/widgets/kotatsu/-/strings/svg-badge.svg)](https://hosted.weblate.org/engage/kotatsu/) [![Telegram](https://img.shields.io/badge/chat-telegram-60ACFF)](https://t.me/kotatsuapp) [![Discord](https://img.shields.io/discord/898363402467045416?color=5865f2&label=discord)](https://discord.gg/NNJ5RgVBC5) [![License](https://img.shields.io/github/license/KotatsuApp/Kotatsu)](https://github.com/KotatsuApp/Kotatsu/blob/devel/LICENSE)
+[![Sources count](https://img.shields.io/badge/dynamic/yaml?url=https%3A%2F%2Fraw.githubusercontent.com%2FKotatsuApp%2Fkotatsu-parsers%2Frefs%2Fheads%2Fmaster%2F.github%2Fsummary.yaml&query=total&label=manga%20sources&color=%23E9321C)](https://github.com/KotatsuApp/kotatsu-parsers) ![F-Droid Version](https://img.shields.io/f-droid/v/org.koitharu.kotatsu) ![Android 5.0](https://img.shields.io/badge/android-5.0+-brightgreen) [![weblate](https://hosted.weblate.org/widgets/kotatsu/-/strings/svg-badge.svg)](https://hosted.weblate.org/engage/kotatsu/) [![Telegram](https://img.shields.io/badge/chat-telegram-60ACFF)](https://t.me/kotatsuapp) [![Discord](https://img.shields.io/discord/898363402467045416?color=5865f2&label=discord)](https://discord.gg/NNJ5RgVBC5) [![License](https://img.shields.io/github/license/KotatsuApp/Kotatsu)](https://github.com/KotatsuApp/Kotatsu/blob/devel/LICENSE)
 
 ### Download
 
 - **Recommended:** Download and install APK from **[GitHub Releases](https://github.com/KotatsuApp/Kotatsu/releases/latest)**. Application has a built-in self-updating feature.
 - Get it on **[F-Droid](https://f-droid.org/packages/org.koitharu.kotatsu)**. The F-Droid build may be a bit outdated and some fixes might be missing.
+- Also [nightly builds](https://github.com/KotatsuApp/Kotatsu-nightly/releases) are available (very unstable, use at your own risk). 
 
 ### Main Features