package icon


Free and open source image board browser
KurobaEx is a fast Android app for browsing imageboards, such as 4chan. It's a fork of Kuroba. This fork provides lots of new features:

* New technological stack (Kotlin, RxJava/Coroutines, Room etc).
* On demand content loading (includes prefetching, youtube videos titles and durations fetching, inlined files size fetching etc).
* Third-party archives support.
* New thread navigation (tabs).
* New in-app navigation (bottom nav bar).
* New bookmarks (they were fully rewritten from scratch, now use way less memory, don't use wakelocks, show separate notifications per thread (and notifications can be swiped away).
* Edge-to-edge theme support.
* New database.
* 4chan global search support.
* Fully dynamic themes with Android Q Day/Night mode support.
* Per-site proxies.
* Ability to attach multiple media files to reply, attach media files that was shared by external apps (event by some keyboards), attach remote media files by URL, etc.
* Lots of other tiny improvements.

- NonFreeNet. The app has to connect to image board sites which may be closed source.
The app may connect to non-free services such as Google ReCaptcha (JS/no-JS), CloudFlare,
GitHub (for some image resources), Youtube/SoundCloud/Streamable (to parse titles and durations),
and other sites. This may depend on the site itself as well as the app settings.

The app uses some permissions that may be considered dangerous:
- RECEIVE_BOOT_COMPLETED. It is used to listen to reboots and reschedule BookmarkWatcher service.
- FOREGROUND_SERVICE. It is used by the service that shows a notification when a file is
downloaded (allows you cancel it).
- WAKE_LOCK. It may be used on Android versions prior to API 23 to keep the device awake while
BookmarkWatcher service is doing it's job.

When making a reply on some sites the app may connect to Google's ReCaptcha services.
The app supports JavaScript and non-JavaScript based captcha systems.
Whether to use a JS or no-JS captcha can be configured in the site settings (depends on the site).

To make the final APK smaller some of the static resources are stored on Github servers and are
loaded lazily, so the app may connect to Github services.

The app uses it's own crash reporting system which is turned on by default.
It collects crash logs and other logs (prior the crash), stores them, but does not upload them
automatically. You have to do it manually. You can see what is being sent and even edit it
(or delete crash logs). You can also completely disable collection of crash logs in the settings.
(The server's source code can be found here


This app has features you may not like. Learn more!


Although APK downloads are available below to give you the choice, you should be aware that by installing that way you will not receive update notifications and it's a less secure way to download. We recommend that you install the F-Droid client and use that.

Download F-Droid
  • Version v0.4.7 (407) - Added on 2021-01-25

    This version requires Android 5.0 or newer.

    It is built and signed by F-Droid, and guaranteed to correspond to this source tarball.

    • have full network access
      Allows the app to create network sockets and use custom network protocols. The browser and other applications provide means to send data to the internet, so this permission is not required to send data to the internet.
    • modify or delete the contents of your shared storage
      Allows the app to write the contents of your shared storage.
    • read the contents of your shared storage
      Allows the app to read the contents of your shared storage.
    • view network connections
      Allows the app to view information about network connections such as which networks exist and are connected.
    • run foreground service
      Allows the app to make use of foreground services.
    • prevent phone from sleeping
      Allows the app to prevent the phone from going to sleep.
    • run at startup
      Allows the app to have itself started as soon as the system has finished booting. This can make it take longer to start the phone and allow the app to slow down the overall phone by always running.

    Download APK 5.6 MiB PGP Signature | Build Log