Comparison

Soulver 4 vs Bindery

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

Head to head
About

Soulver 4

This app combines the functionality of a notepad with a powerful calculator. It allows users to perform complex calculations using natural language, supports unit conversions, date math, and live currency conversions. Organize your calculations in sheets with text comments and share them as PDFs.

Highlights
  • Natural language calculations
  • Unit and currency conversions
  • Date and time math
  • Live currency and stock prices
  • Customizable accessory keyboards
  • Spreadsheet-like line references
  • Variables and conditional statements
Features
Read full description

Ever reach for a calculator and the back of an envelope to work something out? That's what Soulver is for. It's a natural-language notepad calculator: think through a problem line-by-line, using plain words and numbers. The answers appear alongside each line as you type. Soulver isn't just a calculator app — it's the paper you'd scribble on to figure something out. Except this paper does the numbers for you, so you stay thinking at the level of your problem. 20% of $1,480 | $296 $100 in EUR | €86 240 km in miles | 149 mi $1,200 + 15% tax | $1,380 3 weeks from today | June 21 Because Soulver uses sheets (like Notes), you can explore different ideas: weigh options, change variables and watch everything update. WHAT CAN SOULVER CALCULATE? – Live currency conversions — 190 currencies, including crypto – Percentages in plain language — "20% off $50", "$50 is what % of $200" – Unit conversions — hundreds of units across length, weight, volume, data and more – Dates & time — "days until Christmas", time intervals, clock and video-timecode math – Time-zone conversions — "3pm New York to London" – Sums & averages – Financial functions — compound interest, mortgage repayments, hourly rates It's the closest thing to an on-device universal calculator ever created. DESIGNED FOR IPHONE – A meticulously designed numeric keyboard that makes calculating fast – Six specialised accessory keyboards — for currencies, percentages, dates & times, and variables – Build your own custom keyboard with the buttons you reach for most BEST-IN-CLASS ON IPAD – Multiple windows, Slide Over & Split View — float Soulver alongside Notes or Safari – Full Magic Keyboard support with dozens of keyboard shortcuts – Scribble & Apple Pencil – Find & replace, a line-styling palette and a powerful text editor – Automation with URL schemes & Siri Shortcuts POWER USER FEATURES – Multi-word variables — "total cost = $750" – Inline tokenized references to previous answers – Subtotals, tags & trip planning – Wolfram|Alpha integration – Headings, comments, labels & dividers to structure long sheets – Custom units and global variables in the definition sheet SHARING & SYNC – Sync your sheets with Soulver 4 for Mac via iCloud – Export to PDF & plain text, or send beautiful HTML emails – Share a calculation as an image — just take a screenshot ONE TIME PURCHASE Soulver is a one-time (non-subscription) purchase. We've been refining and improving Soulver since 2005, and major paid updates average once every 7 years. Try it free for 60 days, no commitment, no automatic charge. —————————————————————————————— Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Bindery

Features
Read full description

Bindery turns Markdown files into finished documents — Word (.docx), PDF, EPUB and Kobo KEPUB — with a table of contents that actually works: Word's navigation pane, the PDF's outline and contents page, an e-reader's chapter list. Add one file or a dozen chapters at once. The order you put them in is the order of the book: sort by name with a tap, or drag the chapters into place. Headings, lists, tables, code with syntax colouring, footnotes, images, Mermaid diagrams and mathematics all come through, and links between chapters keep working in every format. Everything happens on your device. Your files are not uploaded anywhere; there is no account and nothing to sign in to. Results land in the Files app, under Bindery, ready to share. FREE TO USE Convert up to 20 pages of Markdown a month, free. Bindery Pro removes the limit with a single purchase — no subscription. THE FORMATS • Word (.docx) — real Heading styles and a contents field, bookmarks for every internal link • PDF — an outline, a contents page with page numbers, code blocks that break cleanly across pages • EPUB — one file per chapter, EPUB 3 navigation plus the classic NCX for older readers • Kobo KEPUB — the EPUB with Kobo's own markup, so page counts and reading position work as they should WRITTEN FOR MARKDOWN AS PEOPLE ACTUALLY WRITE IT Two-space list nesting, fenced code inside list items, $…$ mathematics, raw HTML passed through. Where you wrapped a line is not where the reader's is: soft wraps reflow, and only a real line break stays one. Bindery is made by The Owlery Works. Nothing you convert leaves your device. Kobo is a trademark of Rakuten Kobo Inc., and Word is a trademark of the Microsoft group of companies. Neither company is connected with The Owlery Works or has endorsed this app; the names say only what a file is made to open in.

Screenshots

Soulver 44 screens
Bindery4 screens

Verdict

The call

The clearest difference is update cadence: Bindery at fortnightly against Soulver 4's monthly. Soulver 4's advantage is iOS requirement (17.6 vs 26.0). On price, ads, in-app purchases and device support 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. Soulver 4 sells 14 in-app purchases, starting at $26.00 per year and Bindery sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Soulver 4 ships an update monthly, Bindery fortnightly. The most recent releases landed on October 19, 2026 and October 18, 2026 respectively.

Scorecard2 real differences · 8 level
Soulver 4 versus Bindery: the parameters behind the verdict, then further details
ParameterSoulver 4Bindery
PriceFreeFree
Rating4.9 (429 ratings) — better—
Positive reviews76.0% of reviews—
Number of ratings429 — better—
Update frequencyMonthlyFortnightly — better
AdsNoNo
In-app purchasesYesYes
MonetizationPaid—
DevicesiPhone, iPad, Mac — betteriPhone, iPad
Requires iOS17.6 — better26.0
Further details — not scored
Size39 MB76 MB
Age rating4+4+
DeveloperZac CohanDuy Anh Tuan Nguyen

Bugs and requests

Soulver 4

Reported bugs

3 issues
  • Crashes when using certain emojis in sheet titles
  • Issues with iCloud sync and data migration from older versions
  • Inconsistent behavior when modifying variables and formulas

Requested features

4 requests
  • Improved iPad and iPhone UI/UX
  • Enhanced data export and sharing options
  • More advanced mathematical and scientific functions
  • Ability to define custom units and unit conversions

Bindery

Not enough reviews yet to summarise bugs or requests.

In-app purchases

14 purchases

Soulver 4

Subscriptions1
  • AI Assistant, Stocks & Weather$26.001 Year
One-time13
  • Complementary UpgradeFree
  • 30-day free trial (for iPhone)Free
  • 60-day free trial (for iPad)Free
Show 10 more
  • 60-day free trial (for Mac)Free
  • Soulver 4 for iPhone (upgrade)$7.49
  • Soulver 3 for iPhone$14.00
  • Soulver 4 for iPhone$15.00
  • Soulver 3 for iPad$20.00
  • Soulver 4 (Upgrade from Soulver 3)$29.00
  • Soulver 4 (Promotion)$39.00
  • Soulver 3 for Mac$39.00
  • Soulver 4$54.00
  • Soulver 4$59.00
1 purchases

Bindery

One-time1
  • Bindery Pro$3.99

Questions

Is Soulver 4 free?
Soulver 4 is free to download, with in-app purchases available.
Is Bindery free?
Bindery is free to download, with in-app purchases available.
Do Soulver 4 or Bindery have ads?
Neither Soulver 4 nor Bindery shows ads.
Which is updated more often, Soulver 4 or Bindery?
Soulver 4 ships an update monthly, and Bindery fortnightly. Most recently, Soulver 4 was updated on October 19, 2026 and Bindery on October 18, 2026.

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