Android application

The app is available in the Play store.

Architecture

The app is written completely in Kotlin using Jetpack Compose, Dagger/Hilt and aiming to implement a clean architecture.

Module structure

Besides the main app module, the app consists of the following library modules:

• balling
• common
• controller
• feed
• heating
• info
• overview
• refill
• schedule
• timedata
• ventilation

The main app module contains the AndroidManifest and the main activity (As of November 2025, the app only uses one activity). The activity contains the navigation NavHost in onCreate.

None of the other modules has a dependency to the main app module.

The common module provides low-level functionalities and layout elements used in various places. The following functionalities are located in common module:

• DataFetchResult: A wrapper class indicating the status of data fetching operation (Success, Error, Loading, Empty).
• WebApiParams, WebApiPostRequest, WebApiPostRequestExecution, WebApiUrls: Classes and objects used for communication from the app to the server.
• ControllerProfileDao, ControllerProfileDatabase: Classes which provide Room database functionality.
• Various classes used for dependency injection (Hilt)
• SetValsSanityCheckResult: Class used for to communicate status of set values for heating and ventilation module.
• ControllerProfile: Class containing the profile data of the server (address, port, credentials, ...)
• GlobalConstants: Mainly UI-related strings (non-context-related) and some minor functional constants
• Composable functions for the main drop down menu
• Composable functions for the theme
• Composable functions for hyperlinks, text edit fields, headline
• ViewNavigationRoutes: Object containing the routing information processed in main app module
• ScreenshotTestHelper: Helper class for executing the instrumented snapshot testing using the emulator.

Layer structure

The code is separated into the following layers: [module]/ ├── src/main/kotlin/com/laimburggasse/aquariumcontrol/[module]/data/ │ ├── remote/ // Network/API service implementations (e.g., Retrofit) │ │ └── dto/ │ │ └── Dto.kt │ │ └── UserApiService.kt │ ├── repository.kt ├── src/main/kotlin/com/laimburggasse/aquariumcontrol/[module]/domain/ │ ├── model/ // Data Transfer Objects (DTOs) for network/database │ │ └── UserDto.kt │ ├── local/ // Local persistence (e.g., Room DAOs, SharedPreferences) │ │ └── UserDao.kt │ ├── mapper/ // Functions to map DTOs to Domain models and vice-versa │ │ └── UserMapper.kt │ └── repository/ // IMPLEMENTATIONS of the Domain repository interfaces │ └── UserRepositoryImpl.kt // Implements domain.repository.UserRepository └── build.gradle // Dependencies for Room, Retrofit, etc.