OpenAPI Viewer vs API & HTTP Client

OpenAPI Viewer is the easiest way to explore, test, and understand OpenAPI 3.0 and 3.1 specifications on your Apple devices. Whether you're integrating a third-party API, reviewing your team's documentation, or testing endpoints on the go, OpenAPI Viewer gives you a clean, native interface built for developers. EXPLORE YOUR API Open any JSON or YAML OpenAPI file and instantly browse all endpoints organized by tag. Search across operations, schemas, parameters, and examples in seconds. View rich documentation for every endpoint — including descriptions, parameters, request bodies, and responses — with schema constraints, validation rules, and example values displayed clearly. TRY IT OUT Send real HTTP requests directly from the app. Fill in path, query, header, and cookie parameters, provide a request body, configure authentication, and hit Send. View the response body, status code, duration, and validation results — all without leaving the app. EXPORT AND SHARE Copy any request as a cURL command, JavaScript fetch, Swift URLSession, or Python httpx snippet — ready to paste into your terminal or codebase. BUILT FOR APPLE PLATFORMS A thoughtfully designed native UI makes even complex, sprawling APIs easy to read. Color-coded methods, clear badge indicators, and structured layouts — built for Apple platforms from the ground up. FREE TO USE OpenAPI Viewer is completely free with no subscriptions or paywalls. If you find it useful, you can support development through an optional tip jar — entirely your choice. KEY FEATURES • Open JSON and YAML OpenAPI 3.0 and 3.1 specifications • Browse endpoints by tag with HTTP method filters • Full-text search across operations, schemas, examples, and headers • Send real HTTP requests with a built-in inspector • Configure Bearer, API key, Basic, and OAuth credentials • Request history • Copy requests as cURL, fetch, URLSession, or httpx • Schema viewer with constraints, enums, and examples • Native on iPhone, iPad, and Mac

This app is a powerful API Client and API Testing tool built for developers who need to send requests, inspect responses, and debug APIs anytime, anywhere. Whether you're working with REST APIs, GraphQL, WebSockets, or MCP (Model Context Protocol) servers, the app provides everything you need in one place. Test APIs faster, troubleshoot issues efficiently, and analyze responses with an intuitive interface designed for both beginners and experienced developers. - Key Features: + API Client & Request Testing * Send HTTP and HTTPS requests using GET, POST, PUT, DELETE, PATCH, HEAD, and OPTIONS. * Create and edit requests with an intuitive request editor. * View detailed request and response information, including headers, body, status code, response time, payload size, SSL details, and more. * Debug APIs without needing access to your desktop or terminal. + REST API, GraphQL & WebSocket Support * Test and debug REST APIs with ease. * Native GraphQL support with query editor, variables editor, and schema explorer. * Connect to WebSocket servers for real-time communication and testing. + MCP (Model Context Protocol) * Connect to remote MCP servers * Browse available tools, prompts, and resources. * Invoke MCP tools directly from the app. + JSON Viewer & Response Inspector * Automatically format and highlight JSON, HTML, XML, and plain text responses. * Easily inspect API responses for debugging and development. * Filter response data using JSONPath and XPath expressions. + OpenAPI, Swagger & Postman * Import and export Postman Collections and Environments. * Sync collections with your Postman Cloud account. * Support for OpenAPI and Swagger specifications. * Browse API documentation directly inside the app. + Authentication Supports multiple authentication methods, including: * Basic Authentication * Digest Authentication * OAuth 1.0a * OAuth 2.0 * JWT (JSON Web Token) * Additional authentication schemes with secure credential storage. + Productivity * Save reusable variables using Environments. * Import and export collections through iCloud Drive, Dropbox, and other document providers. * Automate API workflows with Apple Shortcuts. Whether you're a backend developer, mobile developer, frontend engineer, QA tester, or DevOps engineer, this app provides a complete solution for API testing, API debugging, REST API development, GraphQL, WebSocket, MCP, and OpenAPI workflows—all from your mobile device.