JSON Viewer, Editor & Format

JSON Viewer is a JSON reader and editor for your phone. Open a file, see exactly where the syntax breaks, fix it, and ask the AI to format or explain the data. XML, YAML, Markdown and SQL open in the same editor with syntax highlighting.

Made for developers, testers and students who get an API response, a config or a data export on the phone and need to read it now.

OPEN AND READ YOUR DATA

• Open a file straight from your phone with the file picker, or paste a payload

• Syntax highlighting, line numbers and word wrap keep long documents readable

• Fold objects and arrays to hide the parts you are not reading

• Find and replace across the whole document

• Light and dark theme, adjustable font size and tab size

CATCH SYNTAX ERRORS

• The validator checks syntax as you type and marks the broken spot

• Typical mistakes are flagged: a trailing comma, a missing quote, an unclosed bracket

• Undo and redo, plus a history of earlier versions

• A smart keyboard bar puts brackets, braces, quotes and colons one tap away

AI FORMATTER AND HELPER

The AI tools run online and need an internet connection.

• Format: pretty print messy or minified data into clean, indented text

• Explain: select a block and ask what the structure means and how to use it in code

• Fix: ask the AI to find and repair a bug; formatted and rewritten code arrives as a diff you can review before applying

• Generate: describe the data you need and get a sample document

• Code review and rewrite for any selection

XML, YAML, MARKDOWN AND SQL

The same editor opens XML, YAML, Markdown and SQL files with highlighting, folding, search and the AI tools. The live check covers JSON only; for the other formats, ask the AI to review them.

20 BUG HUNTS

Missions put you in front of real failures in a simulated terminal and ask you to find the cause:

• A config that fails on line 12 because of a trailing comma

• An API payload rejected for single quotes and bare keys

• Order IDs that collide above 2^53

• A feature flag that is always on because "false" is a string

• Money that is one cent short, a timestamp that moves a day

• An XML conversion that silently drops attributes, an XPath that matches nothing

Easy, medium and hard missions, from commas and quotes to data types, schemas and XML interop.

20 GUIDED PROJECTS

Build real documents step by step: values and the rules of the format, a nested product catalogue, escaping special characters, a config with environment overrides, an API response envelope, JSON Lines for a log file, JSON Pointer, JSON Patch, and schemas from the basics to $defs, $ref, oneOf and if/then/else.

SHARE YOUR WORK

• Copy the result, or share it as a link

• Save snippets and come back to them later

FREE AND PRO

JSON Viewer is free to download. The editor, the syntax check, opening documents and search are free. Free use includes 3 AI requests a day (plus one more for watching a short ad), the first guided project and two missions, and shows ads.

Pro removes ads and unlocks unlimited AI requests, all 20 projects and all 20 missions. Subscriptions renew automatically and can be cancelled any time in your Google Play account settings.

WHO IT IS FOR

• Developers checking an API response away from the desk

• People who need a quick file opener for config files and data exports

• QA testers and analysts reading API payloads

• Students learning how JSON, schemas and XML work

• Anyone who needs to open a .json file on Android and read it

The app is available in 22 languages.

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