# Dev Tool box - Developer Tools — JSON, URL, Base64 & More

> JSON, URL, Base64 & More (iPhone/iPad app by Seonggon Sim.)

- Source: https://appshunter.io/ios/app/dev-tool-box-developer-tools/id6749840624 (this page in markdown: same URL + `.md`)
- Developer: [Seonggon Sim](https://appshunter.io/developer/1565259950)
- Category: Developer Tools, Utilities
- Price: Free
- Age rating: 4+
- Requires: iOS 18.0 · 4 MB
- Languages: American English
- Released: 2025-08-11
- Data updated: 2026-08-26
- User reviews in markdown: https://appshunter.io/ios/app/dev-tool-box-developer-tools/id6749840624/reviews.md

## What is Dev Tool box?

DevToolbox is an essential collection of developer utilities designed to streamline your coding workflow. Whether you're debugging APIs, encoding data, or formatting JSON, DevToolbox provides the tools you need in a clean, native interface.

KEY FEATURES:

• JSON Formatter & Validator
Format, validate, and beautify JSON with syntax highlighting. Tree view visualization for better structure understanding. Built-in search functionality to find text within large JSON files.

• URL Encoder/Decoder
Quickly encode or decode URLs for API testing and web development. RFC 3986 compliant encoding for maximum compatibility.

• Base64 Encoder/Decoder
Convert text to Base64 and vice versa. Supports URL-safe Base64 and auto-padding. Perfect for encoding credentials, tokens, and data URIs.

• JWT Decoder
Decode and inspect JSON Web Tokens without external services. View header, payload, and signature details instantly. Automatically handles "Bearer " prefix.

• Text Case Converter
Transform text between various cases: camelCase, PascalCase, snake_case, kebab-case, SCREAMING_SNAKE_CASE, dot.case, UPPERCASE, lowercase, and Title Case. Smart parsing for any input format.

• Hash Generator
Generate secure hashes using MD5, SHA-1, SHA-256, and SHA-512 algorithms. Essential for checksum verification and security testing.

• Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates. Supports seconds and milliseconds. Multiple output formats including ISO 8601, UTC, and local time.

• Number Base Converter
Convert between Decimal, Binary, Octal, and Hexadecimal. Auto-detects input format with 0x, 0b, 0o prefix support.

• String Escape/Unescape
Escape special characters for JSON strings or unescape encoded text. Handles \n, \t, \", \\ and more.

• Color Converter
Convert HEX colors to RGB and HSL with live preview. Generates ready-to-use SwiftUI, UIKit, and CSS code snippets.

WHY DEVTOOLBOX?

• Native Performance: Built with SwiftUI for blazing-fast performance
• Privacy First: All processing happens locally on your device
• Universal App: Works seamlessly on iPhone, iPad, and Mac
• Dark Mode Support: Easy on the eyes during late-night coding sessions
• No Ads, No Tracking: Just pure functionality
• Offline Ready: No internet connection required

Perfect for mobile developers, web developers, API developers, QA engineers, security professionals, and students learning to code.

DevToolbox is your pocket-sized development companion. Stop switching between websites and online tools - get everything you need in one native app.


## Version history (last 5 releases)

### 1.0.4 — 2026-08-24

Fixed the home screen icon appearing cropped.
Fixed ads failing to load. The number and placement of ads are unchanged.

### 1.0.3 — 2026-02-02

What's New in This Version

New Developer Tools

• Unix Timestamp Converter
  - Convert timestamps to human-readable dates and vice versa
  - Supports both seconds and milliseconds formats
  - Multiple output formats: ISO 8601, UTC, Local time
  - Flexible date input parsing

• Number Base Converter
  - Convert between Decimal, Binary, Octal, and Hexadecimal
  - Auto-detects input format (0x, 0b, 0o prefixes)
  - Clean, organized output for all number bases

• String Escape/Unescape
  - Escape special characters for JSON strings
  - Unescape encoded strings back to readable text
  - Supports \n, \t, \", \\ and more

• Color Converter
  - Convert HEX colors to RGB and HSL
  - Live color preview
  - Ready-to-use SwiftUI and UIKit code snippets
  - CSS variable output

Enhanced Existing Tools

• Base64: Now handles URL-encoded input and auto-adds padding
• JWT Decoder: Automatically removes "Bearer " prefix
• URL Encoder: Stricter RFC 3986 compliant encoding
• Text Case: Added SCREAMING_SNAKE_CASE and dot.case formats
• Text Case: Now correctly parses camelCase and PascalCase input
• Hash Generator: Added SHA-512 output

Improved User Experience

• Colorful menu icons for better visual distinction
• Default example inputs for each tool
• Better error messages with supported format hints

### 1.0.2 — 2025-09-26

What's New in This Version

Enhanced compatibility with iOS 26
Applied Liquid Glass rendering technology for improved visual performance
Optimized system stability and performance

### 1.0.1 — 2025-09-06

What's New in This Version

Enhanced JSON Formatter

• Syntax Highlighting: JSON output now features color-coded syntax for improved readability
  - Keys displayed in blue
  - Strings in green  
  - Numbers in orange
  - Booleans in pink
  - Null values in gray
  - Brackets and braces in purple

• Search Functionality: Quickly find text within your formatted output
  - Real-time search with highlighted results
  - Navigate between multiple matches with previous/next buttons
  - Current match indicator (e.g., "2/5")
  - Keyboard shortcuts on macOS (Cmd+F to search, Cmd+G for next, Cmd+Shift+G for previous)

Improved User Experience
• Better visual distinction between different data types in JSON
• Search highlighting works seamlessly with syntax highlighting  
• Enhanced readability for complex JSON structures

Performance
• Optimized rendering for large JSON files
• Smooth search and navigation experience

### 1.0.0 — 2025-08-12

No release notes.

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All apps by Seonggon Sim: https://appshunter.io/developer/1565259950

## Related topics

[dev tools](https://appshunter.io/ios/topics/dev-tools) · [devbuddy dev tools](https://appshunter.io/ios/topics/devbuddy-dev-tools)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-26.*