The Derpibooru Mobile Client for Android
This app was originally created by deliciousblackink but has not seen updates for some time. This fork aims to continue maintenance and future development of the project with his approval.
The application brings convenient (and fast!) access to the booru on mobile devices. Its user interface follows the Material Design guidelines to create a familiar environment for Android users.
The latest side-load APK can be found here, which contains fix for the launch crash that has been there for some time.
Original releases can be found here, but can be found on the previous link as well.
The minimum Android version required is Ice Cream Sandwich 4.0.3 (API 15).
Take a peek at the main features here.
The project is distributed under the revised (3-clause) BSD license.