Comparison

AddToPDF vs Silo PDF

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

Head to head
About

AddToPDF

Easily edit PDFs on your iPhone or iPad. Scan documents, add text, sign, and fill forms directly on your device. Enjoy a private, offline experience with a one-time purchase.

Highlights
  • Scan documents with camera
  • Add text and signatures
  • Fill PDF forms
  • Reorder, rotate, delete pages
  • Offline functionality
  • One-time purchase
Features
Read full description

Simple PDF editor for iPhone and iPad. Scan a paper document with your camera, or open a PDF from Files, Mail, or any app. Add text, sign it, fill in the form — then send it back. No subscription. No cloud. No account. One purchase covers iPhone, iPad, and Mac. Works fully offline. —— WHAT YOU CAN DO —— • Scan paper documents with the camera — several pages become one PDF. • Open PDFs from Files, Mail, Messages, or any app that can share. • Add text anywhere on the page — type it, then place it with your finger. • Sign with your finger — draw, type, or reuse a saved signature. • Fill existing PDF forms — text fields, checkboxes and dropdowns, detected automatically. • Reorder, rotate, delete and add pages. • Send the finished PDF anywhere — Files, Mail, Messages, or another app. —— MADE FOR YOUR THUMB —— Open a document. Tap what you want to change. That's it. No tutorial, no nested menus, nothing to set up. —— PRIVATE BY DESIGN —— Everything happens on your device. Your documents are never uploaded, and there is no account to create. —— WHO IT'S FOR —— • Anyone who needs to sign a form and send it back, right now • Freelancers and consultants signing contracts on the move • Parents filling in school and medical forms • Anyone tired of paying every month just to edit a PDF —— ABOUT ADDTOPDF —— Made by Mantra Factory — a small studio building simple, honest apps that respect your time. Pay once, use it forever. Requires iOS 14 or later. Works on iPhone and iPad.

About

Silo PDF

Features
Read full description

PDF tools that stay on your phone. Pay once. Use forever. Silo is a private, on-device PDF toolkit for iPhone and iPad. Open a document, edit it, save the result. Nothing is ever uploaded. No account. No subscription. No tracking. Just a fast, focused PDF app that respects what's inside your files. EVERYTHING RUNS ON YOUR DEVICE Open a packet sniffer next to any other PDF tool and watch what happens when you compress a document: your file is uploaded to a server, often in another country. Open one next to Silo and watch nothing happen. Compress, OCR, redact, scan, watermark — every operation runs locally using Apple's own frameworks. Your contracts, tax returns, medical records and client documents never leave your iPhone. ONE PAYMENT. NEVER AGAIN. Most serious PDF apps on iOS are now yearly subscriptions. Silo is a one-time purchase. You pay once and the app is yours — no recurring fee, no expiring license, no surprise "Pro+" tier next year, no upsell screen tucked behind every button. The price you pay is the price. FREE FOREVER • Beautiful PDF viewer with smooth scroll and pinch-zoom • Set Silo as your default PDF viewer on iOS 26 • Recents, search, and Files app integration • Merge multiple PDFs in any order • Split a PDF by range, by count, or by specific pages • Rotate pages, individually or all at once • Convert images to a single PDF PRO TOOLS — UNLOCK ONCE • Document scanner — Apple's edge-detection camera, multi-page output • Compress for email or web with target-size presets • OCR — make scanned PDFs searchable, powered by Apple Vision • Redact — find and remove SSNs, EINs, phone numbers, emails and dates • Reorder and delete pages with drag-to-reorder thumbnails • Password protect with user and owner passwords • Watermark with custom text, opacity, rotation and tiling • Extract selected pages into a new PDF BUILT ON APPLE FRAMEWORKS Silo uses Apple's PdfKit for rendering, the Vision framework for OCR, and VisionKit for the document scanner. There are no third-party PDF servers, no cloud-OCR APIs, no analytics SDKs and no crash reporters that read your file contents. The only network calls Silo makes are to Apple and to RevenueCat to verify your purchase. Both are listed in Settings → Privacy. WHAT SILO WILL NEVER DO Silo has a privacy nutrition label of "Data Not Collected" in the App Store. That's the strongest possible privacy label Apple awards. It means we have no idea who you are, what you've processed, or how you use the app. We can't tell you because we never receive anything. • Upload your files anywhere • Require an account or sign-in • Charge a subscription • Show ads • Track you • Sell your data • Add a paid "Pro+" tier later PRIVACY MANIFEST Silo's privacy manifest declares "App Functionality only" file access with zero data collection. You can verify this in the App Privacy section above. We don't collect names, emails, contacts, identifiers or usage data. We literally cannot see your documents because we never receive them. A NOTE ON LANGUAGE Silo's interface is in English in v1. Tool names and labels are not localized yet. PDF operations themselves are language-agnostic — merge, split, compress, sign and watermark work on documents in any language. The OCR engine is tuned for English; it will pick up other Latin-script languages but accuracy is highest on English text. Pay once. Keep your files. Get back to work.

Screenshots

AddToPDF4 screens
Silo PDF4 screens

Verdict

The call

The clearest difference is price: Silo PDF at Free against AddToPDF's $2.99. AddToPDF's advantage is in-app purchases (none vs 1). On ads, device support and iOS requirement there is nothing between them.

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

CostPrice Ā· In-app purchases Ā· Ads Ā· Monetization

Silo PDF is free to download; AddToPDF costs $2.99 up front. Silo PDF sells 1 one-off in-app purchase. AddToPDF asks for nothing beyond the download.

Scorecard2 real differences Ā· 5 level
AddToPDF versus Silo PDF: the parameters behind the verdict, then further details
ParameterAddToPDFSilo PDF
Price$2.99Free — better
Positive reviews100.0% of reviews—
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaid—
DevicesiPhone, iPad, iPod, Mac — betteriPhone, iPad, iPod
Requires iOS14.0 — better15.1
Further details — not scored
Size6 MB50 MB
Age rating4+4+
DeveloperDENIS SAUVESaulo Marchi

In-app purchases

None

AddToPDF

No in-app purchases

1 purchases

Silo PDF

One-time1
  • Silo Pro: Redact, Watermark$24.99

Questions

Is AddToPDF free?
AddToPDF costs $2.99, with no in-app purchases.
Is Silo PDF free?
Silo PDF is free to download, with in-app purchases available.
Do AddToPDF or Silo PDF have ads?
Neither AddToPDF nor Silo PDF shows ads.

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