Budget+ Multiplatform App（極簡記帳）

Budget+ is an easy-to-use co-spending tracker to track expenses together with your friends and family.

Now available on both Android and iOS!

Feature Overview

Some cool animated features!! ✨

Pie Chart	Color Tone Picker	Customize Color Tone
screen-20240707-170558.2.mp4	screen-20240707-170638.3.mp4	screen-20240707-170638.4.mp4

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Tech Stack

Business Logic and Core

• Kotlin Multiplatform for shared logic across Android and iOS
• Compose Multiplatform for shared UI + MVVM Architecture
• Coroutines & Flow for asynchronous operations
• Metro for dependency injection
• Navigation3 for Composable navigation
• DataStore for persistent data storage
• RevenueCat for in-app purchases and subscriptions
• AdMob with Meta Audience Network mediation for ads
• Kotlinx Serialization for JSON parsing
• Kotlinx Datetime for date and time handling
• Firebase
  • Firestore for real-time database
  • Authentication for Google and Apple ID sign-in
  • Crashlytics for crash reporting
  • Analytics, Messaging, and Remote Config

Open-Source Libraries for KMP

• Coil3 for image loading with KMP support
• Colorpicker-compose for color picking
• Compottie for Lottie animations in Compose Multiplatform
• CrashKiOS for better crash reporting on iOS
• Csv for exporting data as CSV (KMP)
• Detekt for Kotlin static code analysis
• Firebase Kotlin SDK for KMP support
• Kermit for logging
• Keval for mathematical expression evaluation
• MockK for mocking classes in unit tests
• Moko-permissions for KMP permission handling
• Reorderable for reordering items in Compose

Android Specific

• In-App Review and In-App Update integration
• Baseline Profile for improving app startup time

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Supported Deeplinks

• Home screen: https://budgetplus.cchi.tw/record
• Overview: https://budgetplus.cchi.tw/overview
• Unlock premium: https://budgetplus.cchi.tw/unlockPremium
• Settings: https://budgetplus.cchi.tw/settings
• Settings with members dialog: https://budgetplus.cchi.tw/settings?showMembers=true
• Sharing customized color tones: https://budgetplus.cchi.tw/colors?hex=cff1ff%3bdaf2cb%3b84c18f%3b596980

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Performance Optimization (Baseline Profile)

The project uses Baseline Profiles to improve startup performance.

Generating a Profile

To run the generator:

./gradlew :benchmark:connectedReleaseAndroidTest -P android.testInstrumentationRunnerArguments.androidx.benchmark.enabledRules=BaselineProfile

The output can be found in: benchmark/build/outputs/connected_android_test_additional_output/release/connected/[device].

Copy and rename the file to baseline-prof.txt and place it in the src/main directory of the app module.

Running Macrobenchmarks

./gradlew :benchmark:connectedReleaseAndroidTest -P android.testInstrumentationRunnerArguments.androidx.benchmark.enabledRules=Macrobenchmark

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Build the Project Locally

If you want to build the project locally, follow these steps:

1. Clone the repository.
2. Add a google-services.json file under :androidApp folder. Here's a valid dummy file you can use:

{
  "project_info": {
    "project_number": "dummy_project_number",
    "project_id": "dummy_project_id"
  },
  "client": [
    {
      "client_info": {
        "mobilesdk_app_id": "dummy_app_id",
        "android_client_info": {
          "package_name": "com.kevlina.budgetplus"
        }
      },
      "api_key": [
        {
          "current_key": "dummy_api_key"
        }
      ]
    }
  ]
}

3. Now you should be able to build both Android and iOS apps:
   • Build the Android app, run ./gradlew assembleDebug
   • Build the iOS app, run ./gradlew :composeApp:linkDebugFrameworkIosSimulatorArm64
4. If you want to have the app running with real functionalities, you'll need to create a new project on Firebase and wire your API keys in the project.

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Backend: Firebase Cloud Functions

Database interactions and push notifications are implemented using Firebase Cloud Functions.

The backend repository is also open-sourced: budgetplus-cloud-functions

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License

Copyright (c) 2024 Kevin Chiu

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.