giantjson.com

What It Is

GiantJSON Viewer+ is a professional data viewing and debugging tool for Android, focused on local processing of multi-GB JSON, NDJSON, CBOR, MsgPack, HAR, and text log files. It is not just a basic formatter; it brings large-file viewing, HAR network analysis, a REST/GraphQL API Client, query filtering, export, and a Mock Server together on mobile. Its target users include backend engineers, QA, DevOps, and data analysts.

Core Capabilities

The product highlights a native Rust + SIMD core, a streaming architecture, and persistent indexing. It claims to handle files larger than 100GB while avoiding the out-of-memory issues common in Android apps dealing with large files. Viewing modes include a tree-based Browser Mode, a Schema-oriented Structure Mode, and a Text Mode suited to logs and search. Features include JSONPath navigation, bookmarks, hidden paths, Base64 detection, regex search, highlighting, and long-line handling.

The HAR Analyzer can display request counts, transfer size, average response time, error distribution, waterfall charts, domain analysis, and per-request details, and it can clone failed requests into the API Client. The API Client supports REST, GraphQL, Postman Collection import, environment variables, cURL import/export, OAuth 2.0 PKCE, AWS Signature V4, Multipart, and binary request bodies, but it explicitly does not support pre-request or test scripts.

Pricing and Ecosystem

The page only states that a free trial is available and that the app can be downloaded via Google Play; it does not specify subscription, one-time purchase, or premium feature pricing. Ecosystem integrations mainly revolve around Postman, cURL, HAR files exported from Chrome/Firefox/proxies, and exports to TypeScript, JSON Schema, CSV, and SQL. No IDE, CI/CD, or SDK information was found.

Pros, Cons, and Best-Fit Users

Its strengths are that it works offline and locally, with no account required and no cloud upload, making it suitable for handling sensitive API responses, logs, and HAR files. Its mobile feature set is comprehensive, especially useful for troubleshooting on the go or doing quick analysis when a computer is unavailable. The downsides are that the platform appears to be Android-only, while pricing and support channels are not transparent. The API Client also lacks scripting capabilities, so it cannot fully replace advanced Postman automation workflows.

Access from China

Access from mainland China is unknown. The app is distributed via Google Play, so downloading and payment may be affected by the user’s device and network environment. If Google Play is unavailable, alternatives include Postman, Insomnia, Bruno, Hoppscotch, jq, VS Code extensions, or other local JSON/log viewers.