ApiClient

ApiClient is a mobile developer client to test, debug, and manage REST, GraphQL, and WebSocket APIs anytime, anywhere directly on your iOS device.

No need to open your laptop just to test an API endpoint, inspect SSE event streams, test FCM push notifications, or generate code snippets. ApiClient gives you desktop-grade API testing power on mobile.

KEY FEATURES

1. Multi-Protocol API Testing • REST Client: Support for GET, POST, PUT, DELETE, PATCH, HEAD, and OPTIONS. • GraphQL Suite: Dedicated Query and Variables editor with syntax formatting and error handling. • Real-Time WebSockets: Connect to ws:// and wss:// endpoints with live frame logging, custom headers, and message composer. • Live SSE Streaming: Inspect Server-Sent Events in real-time for AI and LLM streaming APIs.

2. Postman & OpenAPI Compatibility • Postman Collections: Support for Postman Collection v1, v2.0, and v2.1 with multi-level nested folders. • OpenAPI / Swagger: Import OpenAPI 2.0 and 3.0 specifications in both JSON and YAML. • 1-Click cURL: Instant cURL import from clipboard and export to cURL.

3. 9-Language Code Generator Convert API requests into clean, ready-to-run code snippets: • Python (requests) • JavaScript (fetch) • Kotlin (OkHttp) • Swift (URLSession) • Dart / Flutter (http) • Go (net/http) • PHP (cURL) • Java (OkHttp) • cURL command

4. Push Notification Tester (FCM HTTP v1) • FCM HTTP v1 support with on-device OAuth2 token generation. • Import Service Account JSON securely or use Bearer tokens. • Custom notification payloads and topic messaging.

5. Session Cookie Manager & Variables • Automatic Cookie Jar captures response Set-Cookie headers. • Domain-grouped cookie inspector with add, edit, and clear capabilities. • Dynamic Variables: Use {{variable}} substitution across URLs, headers, and request bodies.

6. Developer Power Tools • AI Response Diagnostics: Instant offline root-cause troubleshooting for HTTP errors. • JSON Formatter: Beautify and minify JSON with syntax highlighting. • Crypto Suite: Base64 and AES 128/256 Encryption and Decryption utilities. • History & Collections: Auto-saves request history with search, export, and quick replay.

7. Modern UI & Dark Theme • Full Dark and Light theme parity with automatic system theme synchronization. • Clean, responsive interface optimized for all screen sizes.

8. 100% Private & Local-First Your API keys, tokens, requests, and cookies stay strictly on your device. Zero cloud sync, zero telemetry, and zero middleman servers.