Comparison

QuickDoc vs Cairn

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

Head to head
About

QuickDoc

Features
Read full description

Need a clean PDF from a receipt, contract, form, or passport page, and there is no desktop scanner nearby. Doc Copy captures the page, crops the edges, and exports a file you can sign, search, and share from your iPhone or iPad. WHAT DOC COPY DOES Photograph a document and turn it into a PDF in one flow Auto edge detection crops the page and straightens the shot Repair a weak scan by reducing shadows and correcting perspective Sign, merge, watermark, compress, and password protect without a computer Read the page with on device OCR and copy the text Swap an ID photo background and save a print size preset No ads and no account. Open the app and start SCAN TO PDF Capture one page, or keep shooting and build a multi page PDF Import photos from your library and combine them into one document Check the crop, rotate pages, and change the order before you export Save to Files, send by email, or keep a local copy for later Add a home screen widget when you want to jump back into a scan PDF TOOLS FOR REAL PAPERWORK Merge several PDFs into one file Extract only the pages you need Rotate, delete, and reorder pages Add page numbers Compress a large file so it is easier to email Place a handwritten signature Add a text or image watermark Encrypt a PDF with a password Remove a password from a PDF you are allowed to open Export pages as JPG or PNG images Stitch pages into one long image Resize a photo when a form asks for a specific size TEXT YOU CAN USE OCR runs on your device and pulls text off a scanned page Rebuild a scan as a searchable PDF so you can find and copy words later Send a recognized table to CSV or Excel Export recognized text as a file that opens in Word ID PHOTO Change the background to white, blue, red, gray, or cyan Pick a common print size, including a passport preset Save the finished photo to your library PRIVATE BY DESIGN Scanning, cropping, OCR, and PDF edits run on your device. Doc Copy does not upload your documents to our servers. Your library stays on the phone or tablet, with folders, favorites, and search Lock the app with Face ID or Touch ID when the paperwork is sensitive ONE PURCHASE, NOT A SUBSCRIPTION Pro is a single unlock. It opens the full PDF toolkit and ID photo tools, and it removes the camera to PDF page limit. The price is shown on the App Store before you pay. Restore the purchase on a new device with the same Apple ID. BEFORE YOU SEND A FILE Doc Copy helps you make personal copies and packets to share. A landlord, bank, school, clinic, or government office may require a specific size or format. Confirm their rules before you submit. ID photo presets are print sizes, not a promise that any agency will accept the photo. Download Doc Copy and turn the page in front of you into a PDF you can sign, search, and send.

About

Cairn

Track important upcoming dates and past anniversaries with a versatile countdown and count-up tool. It offers precise timing, customizable reminders, and various visual displays to keep you informed. Integrates seamlessly with your devices and data.

Highlights
  • Countdown and count-up for any event
  • Minute and second precision timing
  • Customizable repeat intervals
  • Time zone support
  • Visual progress tracking
  • Milestone markers
  • Home and Lock Screen widgets
Features
Read full description

Cairn counts down to the days you're waiting for, and counts up from the days you don't want to forget. Give it a date. It answers in days — 124 days to go, or 1,024 days since. Everything else gets out of the way. COUNTDOWN AND COUNT-UP, ONE MODEL • Days to go for anything ahead: a holiday, a trip, an exam, a due date • Days since anything behind: an anniversary, a baby's birth, the day you quit • Turn on minute precision when the hour matters — "3 days 4 hours", with seconds only in the final hour • Repeat yearly, monthly, weekly, every N days, or by the lunar calendar • Every event carries its own time zone, so flying across the world never shifts the number • Count only working days when a countdown is about business days • A date calculator for the days between two dates, or a date N days away — save the answer as an event • Pick up dates from a screenshot, a photo or a bit of text, and start a new event already filled in SEE WHERE IT STANDS • A countdown bar reads like a battery gauge: solid is what's left, full to empty • A count-up grid fills one square at a time, a day at a time • Milestones at 100, 365, 520, 1,000 and 1,314 days, marked right on the track • Ring, milestone track or heat grid — pick one per event, or just keep the number • A year view lays out all twelve months at once, so you can see which one is crowded; a month view lays them out day by day • Yearly events show which anniversary it is, and the day a countdown reaches zero gets a small celebration REMINDERS THAT ARRIVE ON TIME • Several reminders per event: days, weeks or months ahead, at the hour you choose • A daily digest each morning for what's today and what's this week • Live Activity and Dynamic Island for the last 24 hours • Time-sensitive delivery for the dates that shouldn't wait behind a Focus EVERYWHERE YOU LOOK • Home Screen widgets in small, medium and large: one event, a list, or a chart • Lock Screen widgets — inline, circular and rectangular — each pointed at the event you choose • An Apple Watch app and complications: circular, rectangular, inline and corner • A Control Center control for a new countdown in one tap • Ask Siri how long until anything, or find an event right from Spotlight • Share an event with family or friends: change the date and it changes for them too YOURS, AND ONLY YOURS • No account. Nothing to sign up for. • Syncs across iPhone, iPad and Mac through your own iCloud, and mirrors to Apple Watch from your iPhone • Import dates from Calendar and birthdays from Contacts — read only, never written back • Export everything to a single JSON file and import it back whenever you like; local snapshots and Recently Deleted bring back what you removed by mistake • App Lock asks for Face ID, Touch ID or your passcode when you come back • Cover photos with automatic tinting, six muted themes, categories, pinning, archiving and a share card • English, Simplified and Traditional Chinese, Japanese, Korean, German, Spanish and Brazilian Portuguese — dates and month names included Cairn is a one-time purchase. No in-app purchases, no subscription, no ads, no tracking. A cairn is the pile of stones a trail keeps stacking to mark the way — one for every stretch you have walked.

Screenshots

QuickDoc3 screens
Cairn4 screens

Verdict

The call

The clearest difference is price: QuickDoc at Free against Cairn's $0.99. QuickDoc also leads on iOS requirement (17.6 vs 26.0). Cairn's advantage is in-app purchases (none vs 1) and update cadence (weekly vs every 2 months). On ads 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

QuickDoc is free to download; Cairn costs $0.99 up front. QuickDoc sells 1 one-off in-app purchase. Cairn asks for nothing beyond the download.

UpkeepUpdate frequency

QuickDoc ships an update every 2 months, Cairn weekly. The most recent releases landed on October 8, 2026 and October 9, 2026 respectively.

Scorecard5 real differences · 5 level
QuickDoc versus Cairn: the parameters behind the verdict, then further details
ParameterQuickDocCairn
PriceFree — better$0.99
Rating—5.0 (1 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—1 — better
Update frequencyEvery 2 monthsWeekly — better
AdsNoNo
In-app purchasesYesNo — better
Monetization—Free
DevicesiPhoneiPhone, iPad, Apple Watch — better
Requires iOS17.6 — better26.0
Further details — not scored
Size11 MB8 MB
Age rating4+4+
Developer友健 高飞 吕

In-app purchases

1 purchases

QuickDoc

One-time1
  • Upgrade to premium$1.99
None

Cairn

No in-app purchases

Questions

Is QuickDoc free?
QuickDoc is free to download, with in-app purchases available.
Is Cairn free?
Cairn costs $0.99, with no in-app purchases.
Do QuickDoc or Cairn have ads?
Neither QuickDoc nor Cairn shows ads.
Which is updated more often, QuickDoc or Cairn?
QuickDoc ships an update every 2 months, and Cairn weekly. Most recently, QuickDoc was updated on October 8, 2026 and Cairn on October 9, 2026.

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