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For iPhone, iPad and Mac

Forty-two developer tools. Not one network request.

DevKit is the toolbox you already keep open in a browser tab — JSON, JWTs, regex, hashes, cron and more — rebuilt as a native app that works with the radio off.

On the App StoreSearch for “DevKit: Developer Toolbox”

Browse all 42 tools

Free to download · Twelve tools free forever · iOS 17, iPadOS 17 and macOS 14

JSON Format on Mac in dark mode: minified JSON as input, and the same JSON validated and pretty-printed as output.
DevKit on iPhone: the Tools screen, with search across 42 tools, the Paste to detect banner and the Data Formats tools.

  • 42

    developer tools, all running on your device

  • 12

    of them free forever, with no account and no time limit

  • 0

    network requests — not a setting, but how the app is built

  • 3

    platforms covered by one purchase: iPhone, iPad and Mac

Smart paste

Paste anything. DevKit knows what it is.

Tap paste and DevKit recognises the shape of what you gave it — a token, a certificate, a cron line, a colour — and offers the tools that fit, best first.

  • It never reads your clipboard on its own. You tap paste; it looks. That is why iOS never interrupts you with a paste permission prompt.

  • From any app, with Pro. The share sheet on iPhone and iPad, and Services on a Mac, recognise selected text in place.

  1. eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdW…

    JWT Decode

    A JSON Web Token

    Free
  2. */15 9-17 * * MON-FRI

    Cron Parser

    A cron schedule

    Pro
  3. 192.168.1.0/24

    IP / CIDR

    An IP network

    Pro
  4. #4B7BEC

    Color Convert

    A colour

    Free
  5. 1735689600

    Unix Time

    A Unix timestamp

    Free
  6. -----BEGIN CERTIFICATE-----

    Certificate Decode

    An X.509 certificate

    Pro
  7. SELECT a FROM t WHERE b = 1

    SQL Format

    A SQL query

    Pro
  8. {"a":1,"b":[2,3]}

    JSON Format

    JSON

    Free

iPhone, iPad and Mac

Native on every screen you work on.

The same forty-two tools wherever you are, with a layout built for each device rather than stretched across them.

JWT Decode on iPad, with the sidebar, the token and its options, and the decoded header, payload and claims.

  • Native, not a web view

    Built in SwiftUI for iPhone, iPad and Mac, and it looks and behaves like it belongs on each.

  • Made for the keyboard

    Search and keyboard shortcuts on iPad and Mac, and a menu bar popover on macOS.

  • One purchase, every device

    DevKit is a Universal Purchase. Pro on your iPhone is Pro on your Mac.

Built for how you work

Out of the app, into your workflow.

History on iPhone: recent runs of JSON Format, JWT Decode, Base64, Hash and Unix Time, noting that the free tier keeps the last 20 runs.

  • Every tool is a Shortcuts action

    Compose tools into automations that run without opening the app, with ten Siri phrases for the most-used ones.

  • Pro

    Share extension and Services

    Send selected text from any app to the right tool — the share sheet on iPhone and iPad, Services on a Mac.

  • Pro

    Home Screen widgets

    The current epoch time at a glance, and a one-tap launcher for the tool you use most.

  • A menu bar popover

    On a Mac, search and open any tool from the menu bar, then get straight back to work.

  • History, favourites and drafts

    Pin the tools you use and pick up where you left off. Free keeps your last 20 runs; Pro keeps them all.

  • Pro

    iCloud sync

    Favourites and history on every device, in your own private iCloud database. Drafts never sync, deliberately.

JWT Decode on iPhone: a token with its options, and notes saying the token has not expired and its signature was not checked.

Honest tools

A decoded token is not a trusted token.

DevKit tells you what it found and what it did not check. Reading a JWT or a certificate shows you what is in it, not whether to believe it — and the app says so, right where it matters.

  • Bounded, so nothing hangs

    A 5 MB ceiling on input, depth limits on every recursive parser, and a regex tester that gives up after two seconds instead of wedging.

  • Fuzzed on every build

    All 42 tools face empty input, control characters, deeply nested structures, script tags and SQL injection strings. Anything but a clear error fails the build.

  • A preview that cannot phone home

    The HTML preview runs with JavaScript off, blocks every resource load and cancels every navigation.

Read the security model

Privacy

Private by construction, not by a setting.

DevKit makes no network requests. On a Mac it does not even hold the entitlement that would allow one. Turn on Airplane Mode: everything still works.

  • No network requests

    Everything you paste is processed on your device.

  • No account

    Nothing to sign up for, and nothing to sign in to.

  • No analytics or tracking

    No telemetry and no advertising identifier. The App Store label reads Data Not Collected.

  • No third-party code

    No SDKs and no dependencies, so there is nothing else to trust.

History stays on your device and its previews can be switched off. Settings → Erase all data removes everything, including anything synced to your own private iCloud.

Read the privacy policy
Settings on iPhone: Store previews in history switched on, Sync with iCloud switched off, and a note that DevKit makes no network requests.

Free and Pro

Twelve tools free. Forever.

No account and no time limit. DevKit Pro adds the other thirty tools, unlimited history, iCloud sync, widgets, and the share extension and Services.

  • JSON Format
  • Base64
  • URL Encode
  • JWT Decode
  • UUID Generate
  • Unix Time
  • Hash
  • Regex Tester
  • Color Convert
  • String Case
  • Number Base
  • Text Diff

Pro is $1.99 a month or $12.99 a year, each with a 7-day free trial for new subscribers — or $24.99 once. One purchase covers iPhone, iPad and Mac.

US prices. The App Store shows yours in your own currency.

Compare Free and Pro

Your whole toolbox, with the radio off.

Free on the App Store for iPhone, iPad and Mac.

On the App StoreSearch for “DevKit: Developer Toolbox”