API Tester - REST HTTP Client is a versatile mobile application designed for testing various types of APIs directly from your Android device. It supports a wide range of protocols, including REST, GraphQL, WebSocket, SOAP, and more. Users can perform all types of HTTP requests such as GET, POST, PUT, and DELETE, among others. The app features a powerful GraphQL editor equipped with a body editor for queries and mutations, a variables editor, and request settings to facilitate a comprehensive testing experience.

Additionally, API Tester offers tools for WebSocket testing, allowing users to manage connections and message exchanges seamlessly. The app supports multiple data encoding methods, including query parameters and raw data uploads. Users can customize settings for TLS, redirects, and timeouts, and can easily import requests from various formats. With features like request metrics, history tracking, and integration options for shortcuts and widgets, API Tester stands out as a robust utility for developers needing on-the-go API testing capabilities.