CatalogApp is a high-performance product discovery engine built to showcase modern Android engineering excellence. It solves the challenge of high-speed product browsing by combining Predictable State Management, Adaptive Layouts, and Advanced Performance Compilations.
This project is built following the Stitch Design System, ensuring a professional, consistent, and user-centric visual experience.
- Adaptive Layouts: Full support for Phone, Foldable, and Tablet form factors.
- Dynamic Theming: Native support for Light and Dark Mode, automatically respecting system-wide preferences.
| Product Catalog | Product Search | Product Detail |
|---|---|---|
 |
 |
 |
Note
The UI natively supports both Light and Dark Mode as well as Adaptive Layouts for Phone, Foldable, and Tablet form factors.
The project follows a Feature-Modular Clean Architecture. This ensures that the codebase is ready for large-team development by enforcing strict boundaries between modules.
:app: The DI root and Navigation coordinator.:feature:*: Pure UI modules (Catalog, Detail, Search) with MVI ViewModels.:domain:product: The "Brain" — Framework-free business logic and entities.:data:product: The "Heart" — SSOT Repository implementation with Room + Retrofit.:core:*: Common infrastructure (Network, Design System, Shared Utils).
graph TD
APP[":app"] --> FEAT[":feature:catalog"]
APP --> DETAIL[":feature:detail"]
FEAT --> DOMAIN[":domain:product"]
DATA[":data:product"] --> DOMAIN
DATA --> NET[":core:network"]
FEAT --> DSYS[":core:designsystem"]
The app doesn't just "show data"; it manages a complex lifecycle of synchronization and caching to ensure a zero-latency user experience.
- SSOT Pattern: The UI only ever observes the Room Database.
- Smart Refresh: Implements a 30-minute stale-check logic to prevent unnecessary network calls while keeping data fresh.
- Background Sync: Uses WorkManager with
CoroutineWorkerto handle data synchronization even when the app is backgrounded. - Connectivity Awareness: A structured
ConnectivityCheckerprevents UI hangs during network transitions.
sequenceDiagram
participant UI as Compose UI
participant VM as ViewModel
participant Repo as Repository
participant DB as Room Local
participant API as Retrofit API
UI->>VM: User Intent (Refresh)
VM->>Repo: syncProducts()
Repo->>API: GET /products
API-->>Repo: ProductDTOs
Repo->>DB: Upsert (Single Transaction)
DB-->>UI: Reactive Flow Update
This project moves beyond standard development by implementing deep-level optimizations:
- Baseline Profiles: Custom rules ensure the AOT (Ahead-of-Time) compiler optimizes the most critical user journeys (Catalog grid rendering and transitions).
- Macrobenchmarks: Quantitative verification of Startup and Jank metrics using the
androidx.benchmarklibrary.
- Stability Configuration: Explicitly marks domain models as
@Stableviacompose-stability.conf, allowing the Compose compiler to skip recompositions for these types. - Adaptive Grid: A responsive grid that uses
GridCells.Adaptive(minSize = 128.dp), ensuring the layout is perfect on a phone (2 columns) or a tablet (4+ columns). - TTFD Signaling: Uses
ReportDrawnWhento communicate with the OS when the content is interactive, providing real-world performance telemetry.
| Category | Technology |
|---|---|
| Language | Kotlin 2.2.10 (Strongly typed, Coroutines, Flow) |
| UI Framework | Jetpack Compose (Material 3, Adaptive Grid, Dark/Light Mode) |
| Navigation | Navigation 3 (Type-safe routing via Kotlin Serialization) |
| Dependency Injection | Hilt (Dagger-based DI for Android) |
| Database | Room (SQLite abstraction with Flow support) |
| Networking | Retrofit 2 + OkHttp 4 + Gson |
| Image Loading | Coil (Kotlin Image Loading with Coroutines) |
| Analysis | Detekt (Static Analysis), JaCoCo (Test Coverage) |
- Static Analysis:
Detektintegrated with custom rules to maintain high code quality. - Coverage Enforcement:
JaCoCopipeline ensuring 75%+ coverage on critical Domain and ViewModel logic. - Dependency Injection: Full Hilt integration with Assisted Injection for Workers.
- Type-Safe Navigation: Using the latest Navigation 2.8+ features with Kotlin Serialization routes.
If you're reviewing this for my interview, let's discuss:
- Skipping Recompositions: How I audited the UI with the Stability Config.
- Modularization Strategy: Why I separated Domain from Data in a portfolio-sized project.
- Adaptive UI Strategy: Why I chose
minSizeover hardcoded column counts. - Resilience: How the
catchoperators in my Repository Flows prevent UI crashes during sync failures.
Developed for the Senior Android Portfolio 2026.