Comparison

API Tool Pro vs OpenAPI Viewer

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

API Tool Pro

Features
Read full description

Network Stream Test is a powerful and user-friendly tool for developers and testers. Effortlessly create, send, and manage HTTP and WebSocket requests, view detailed responses, and organize your API calls with tabs, history, and collections. The app also supports network stream testing, including m3u8 (HLS) video playback, making it ideal for streaming developers. Features include file and image upload, environment variable management, authentication support, and a modern, customizable interface with light and dark themes. Perfect for debugging, learning, and streamlining your API and streaming workflow. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

OpenAPI Viewer

Features
Read full description

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

Screenshots

API Tool Pro4 screens
OpenAPI Viewer3 screens

Verdict

The call

The clearest difference is in-app purchases: API Tool Pro at none against OpenAPI Viewer's 3. API Tool Pro also leads on update cadence (every 3 days vs every 2 weeks) and iOS requirement (12.0 vs 18.1). On price, ads and device support there is nothing between them.

Scored on Price Ā· Rating Ā· Positive reviews Ā· Number of ratings Ā· Update frequency Ā· Ads Ā· In-app purchases Ā· Monetization Ā· Best chart rank Ā· Devices Ā· Requires iOS

CostPrice Ā· In-app purchases Ā· Ads Ā· Monetization

Both are free to download. OpenAPI Viewer sells 3 one-off in-app purchases. API Tool Pro asks for nothing beyond the download.

UpkeepUpdate frequency

API Tool Pro ships an update every 3 days, OpenAPI Viewer every 2 weeks. The most recent releases landed on September 29, 2026 and October 5, 2026 respectively.

Scorecard3 real differences Ā· 3 level
API Tool Pro versus OpenAPI Viewer: the parameters behind the verdict, then further details
ParameterAPI Tool ProOpenAPI Viewer
PriceFreeFree
Update frequencyEvery 3 days — betterEvery 2 weeks
AdsNoNo
In-app purchasesNo — betterYes
DevicesiPhone, iPad, iPodiPhone, iPad, Mac
Requires iOS12.0 — better18.1
Further details — not scored
Size37 MB13 MB
Age rating4+4+
DeveloperAshen Ishanka CosthaVictor Manuel Puga Ruiz

In-app purchases

None

API Tool Pro

No in-app purchases

3 purchases

OpenAPI Viewer

One-time3
  • Small Tip$1.99
  • Medium Tip$4.99
  • Large Tip$9.99

Questions

Is API Tool Pro free?
API Tool Pro is free to download, with no in-app purchases.
Is OpenAPI Viewer free?
OpenAPI Viewer is free to download, with in-app purchases available.
Do API Tool Pro or OpenAPI Viewer have ads?
Neither API Tool Pro nor OpenAPI Viewer shows ads.
Which is updated more often, API Tool Pro or OpenAPI Viewer?
API Tool Pro ships an update every 3 days, and OpenAPI Viewer every 2 weeks. Most recently, API Tool Pro was updated on September 29, 2026 and OpenAPI Viewer on October 5, 2026.

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