Comparison

JSON Master vs OLM Converter · Viewer, Reader

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

Head to head
About

JSON Master

This offline iOS tool formats, views, validates, and converts JSON data. It supports large files and offers privacy-safe, local processing for developers needing to debug API responses or transform data formats.

Highlights
  • Offline JSON formatting and beautifying
  • Tree and text view for JSON visualization
  • Instant JSON syntax validation
  • JSON to CSV, XML, Excel conversion
  • Large file support
  • Import from clipboard and files
Features
Read full description

JSON Master is a professional JSON Formatter / Viewer / Converter for developers (offline iOS tool). Three key points upfront: 100% offline processing, privacy-safe, large file support — your data is never uploaded to any server. Core Features (Developer Favorites): JSON Formatter & Beautifier: One-click format/beautify/minify, with syntax highlighting support. JSON Viewer: Tree View / Text views for clear structure visualization. JSON Validator: Instant syntax error detection (with line numbers) for quick API response debugging. Fast Converter: Bidirectional JSON ↔ CSV / XML / Excel (.xlsx) conversion. Large File Support: Smoothly open and edit large files. Import Anywhere: Import from Clipboard / Files for debugging anytime. Why Choose JSON Master? • Privacy First: All formatting, validation, and conversion happen locally on your device. • Focused & Distraction-Free: Clean interface with no redundant steps, perfect for quick data inspection and fixing. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://legal.rkvpxdr.com/privacy.html

About

OLM Converter · Viewer, Reader

Easily open, read, and convert Outlook for Mac archive files (.olm) on your devices. Browse mail, contacts, calendars, and tasks, then export them to various formats like MBOX, PDF, and CSV without needing Outlook.

Highlights
  • Open .olm archives without Outlook
  • Read mail, contacts, calendar, notes, tasks
  • Browse full folder tree
  • Search mail by subject, sender, text
  • Convert to MBOX, EML, PDF, CSV, HTML, vCard, ICS
  • Export entire mailboxes or selected folders
  • Works offline on device
Features
Read full description

Have an OLM file you cannot open? OLM Converter opens Outlook for Mac archives right on your Mac, iPhone, and iPad, lets you read everything inside, and converts it to the formats you actually use. Open a .olm export, browse every folder, and read your mail, contacts, calendar, notes, and tasks. Then convert and export the parts you need, all on your device. WHAT YOU CAN DO • Open and read .olm archives from Outlook for Mac, no Outlook needed • Browse the full folder tree, and search mail by subject, sender, or text • View contacts, calendar events, notes, and tasks • See every attachment and save it to Files • Convert and export to MBOX, EML, CSV, PDF, HTML, vCard, and ICS • Export a whole mailbox, or just the folder you choose EXPORT FORMATS • MBOX, or a zipped folder tree of MBOX files • EML, one message per file, with the folder structure preserved • PDF for reading and sharing • CSV of the message list • A browsable HTML archive • vCard (.vcf) contacts and ICS (.ics) calendar events BUILT RIGHT • Runs on Mac, iPhone, and iPad • Everything happens on your device. Your archive never leaves it • No account, no sign in, nothing is uploaded • Handles large, multi gigabyte archives • Fast, reliable, and faithful to the original PERFECT FOR • Opening an .olm file on your Mac without Outlook • Anyone moving away from Outlook for Mac • Moving your mail into another app that reads MBOX or EML, such as Apple Mail or Thunderbird • Archiving, exporting, or simply reading an old .olm file OLM Converter is an independent app and is not affiliated with, endorsed by, or sponsored by any email software vendor. OLM and Outlook are referenced only to indicate the file format the app works with. Privacy Policy: https://rush.tools/privacy Terms of Use: https://rush.tools/terms

Screenshots

JSON Master3 screens
OLM Converter · Viewer, Reader4 screens

Verdict

The call

The clearest difference is review sentiment: JSON Master at 100% against OLM Converter · Viewer, Reader's 0%. OLM Converter · Viewer, Reader's advantage is ads (none vs shown). On price, update cadence, in-app purchases and monetization model there is nothing between them.

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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. JSON Master sells 3 in-app purchases, starting at $2.99 per 7 days and OLM Converter · Viewer, Reader sells 3 in-app purchases, starting at $4.99 per 7 days. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

JSON Master ships an update every 9 days, OLM Converter · Viewer, Reader every 5 days. The most recent releases landed on October 3, 2026 and October 5, 2026 respectively.

Scorecard2 real differences · 8 level
JSON Master versus OLM Converter · Viewer, Reader: the parameters behind the verdict, then further details
ParameterJSON MasterOLM Converter · Viewer, Reader
PriceFreeFree
Rating4.6 (5 ratings) — better—
Positive reviews100.0% of reviews — better0.0% of reviews
Number of ratings5 — better—
Update frequencyEvery 9 daysEvery 5 days — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod, Mac — better
Requires iOS15.015.0
Further details — not scored
Size41 MB24 MB
Age rating4+4+
DeveloperTianjin Illuso Information Technology Co., Ltd.Rush Tools LLC

Customer experience

JSON Master

All ratings5 ratings
Positive80.0%
Neutral20.0%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

OLM Converter · Viewer, Reader

Written reviews1 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

In-app purchases

3 purchases

JSON Master

Subscriptions2
  • JSON Master Pro (Weekly)3 Days trial$2.997 Days
  • Pro (Yearly)$14.991 Year
One-time1
  • JSON Master Pro Lifetime$17.99
3 purchases

OLM Converter · Viewer, Reader

Subscriptions2
  • Pro Weekly$4.997 Days
  • Pro Annual$39.991 Year
One-time1
  • Pro Lifetime$59.99

Questions

Is JSON Master free?
JSON Master is free to download, with in-app purchases available.
Is OLM Converter · Viewer, Reader free?
OLM Converter · Viewer, Reader is free to download, with in-app purchases available.
Do JSON Master or OLM Converter · Viewer, Reader have ads?
JSON Master shows ads; OLM Converter · Viewer, Reader does not.
Which is updated more often, JSON Master or OLM Converter · Viewer, Reader?
JSON Master ships an update every 9 days, and OLM Converter · Viewer, Reader every 5 days. Most recently, JSON Master was updated on October 3, 2026 and OLM Converter · Viewer, Reader on October 5, 2026.

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