Your phone contains some of your most sensitive information: tax returns, bank statements, medical records, IDs, and contracts. If your phone is lost, stolen, or hacked, this data could be exposed.

Here’s how to store sensitive documents securely.

The Risk is Real

What’s at Stake

Consider what’s on your phone:

  • Tax returns — Social security numbers, income, employer info
  • Bank statements — Account numbers, transaction history
  • Medical records — Health conditions, prescriptions, insurance
  • IDs — Passport, driver’s license, birth certificate scans
  • Contracts — Signatures, personal details, legal agreements

A data breach or phone theft could lead to:

  • Identity theft
  • Financial fraud
  • Privacy violations
  • Blackmail

Common Mistakes

Storing documents in camera roll — No encryption, often backed up unencrypted

Using unsecured cloud storage — Documents accessible to anyone with your password

Email attachments — Emails are rarely encrypted, often stored indefinitely

Unnamed files — Files like “IMG_4521.pdf” containing sensitive data are hard to secure


Security Principles for Documents

1. Encryption

Encryption scrambles your data so only you can read it. Two types matter:

TypeWhat It ProtectsExample
Encryption at restData stored on deviceYour phone’s file system
Encryption in transitData being sentHTTPS, TLS
End-to-end encryptionData everywhereOnly you hold the keys

Best practice: Use apps with end-to-end encryption for cloud backup. Scanify PDF uses AES-256 encryption — your documents are encrypted before leaving your phone.

2. Access Control

Who can access your documents?

  • Device lock — PIN, password, biometric
  • App lock — Additional protection for sensitive apps
  • File encryption — Password-protected individual files

3. Backup Strategy

The 3-2-1 rule:

  • 3 copies of important data
  • 2 different storage types
  • 1 off-site (cloud) backup

How to Secure Your Documents

Step 1: Use a Secure Document App

Don’t store sensitive documents in:

  • Camera roll
  • Notes app
  • Random cloud folders

Instead, use a dedicated document app with security features:

What to look for:

FeatureWhy It Matters
EncryptionProtects data even if accessed
App lockBiometric/password protection
Encrypted backupSecure cloud storage
On-device processingDocuments don’t leave your phone

Recommended: Scanify PDF — AES-256 encrypted backup, optional app lock, on-device OCR processing.

Step 2: Enable Device-Level Security

Your first line of defense is your phone itself:

iPhone:

  1. Settings → Face ID & Passcode
  2. Enable Face ID (or Touch ID)
  3. Use a 6-digit PIN minimum (or alphanumeric password)
  4. Enable “Erase Data” after 10 failed attempts

Android:

  1. Settings → Security
  2. Enable fingerprint or face unlock
  3. Use a strong PIN or password
  4. Enable device encryption (usually default)

Step 3: Use App Lock for Sensitive Apps

Add an extra layer beyond device lock:

Many document apps (including Scanify PDF) support:

  • Biometric lock (fingerprint, face)
  • PIN/password lock
  • Auto-lock after timeout

Even if someone accesses your unlocked phone, they can’t open your documents.

Step 4: Enable Encrypted Cloud Backup

Not all cloud backup is equal:

Backup TypeSecurity Level
Standard cloud sync⚠️ Provider can access your files
Password-protected sync⚠️ Better, but keys held by provider
End-to-end encryption✅ Only you can decrypt

Scanify PDF encrypts documents with AES-256 before uploading to Google Drive. Even if someone accesses your Drive, they see encrypted files only.

Step 5: Create Password-Protected PDFs

For extra-sensitive documents, add PDF-level password protection:

  1. Scan document with Scanify PDF
  2. When exporting, enable “Password protect”
  3. Set a strong password
  4. Even if the file is shared, it requires the password to open

Use strong passwords:

  • 12+ characters
  • Mix of upper, lower, numbers, symbols
  • Don’t reuse passwords

What Documents Need Extra Security?

🔴 High Sensitivity (Encrypt + App Lock + Password)

  • Social Security cards
  • Tax returns
  • Passport / visa
  • Birth certificate
  • Financial statements
  • Medical records
  • Legal contracts
  • Power of attorney documents

🟡 Medium Sensitivity (Encrypt + App Lock)

  • Utility bills
  • Employment contracts
  • Insurance policies
  • Property documents
  • Vehicle titles

🟢 Low Sensitivity (Basic encryption)

  • General receipts
  • Warranties
  • Manuals
  • Non-sensitive correspondence

Security Features to Look For

When choosing a document storage app, prioritize these features:

Must-Have

FeatureDescription
AES-256 encryptionIndustry-standard encryption for backups
App lockBiometric or PIN protection
On-device processingOCR and processing happen locally
Secure cloud backupEncrypted before upload

Nice-to-Have

FeatureDescription
Password-protected PDFsExtra protection for sharing
Auto-lock timeoutLocks app after inactivity
No third-party serversBackup directly to your own cloud
Zero-knowledge encryptionEven the app maker can’t see your data

Scanify PDF Security Features

Scanify PDF includes:

AES-256 encryption for Google Drive backup
Biometric app lock (fingerprint, face)
On-device OCR — documents never leave your phone for processing
Password-protected PDF export
Direct Google Drive backup — no third-party servers
Offline-first — works without internet


Common Security Mistakes

❌ Sharing Documents Insecurely

Don’t send sensitive documents via:

  • Regular SMS/text
  • Unencrypted email
  • Social media messaging

Instead: Use password-protected PDFs, secure messaging apps, or encrypted file sharing.

❌ Using Weak Passwords

“Password123” is cracked instantly. Use:

  • 12+ characters
  • Random words (passphrase)
  • Password manager

❌ Not Backing Up

Device theft, loss, or damage can destroy your only copies. Always have encrypted backups.

❌ Ignoring App Permissions

Check what permissions your document app requests. Be wary of:

  • Contacts access (not needed for scanning)
  • Location access (not needed for scanning)
  • Excessive storage permissions

❌ Using Outdated Apps

Security vulnerabilities get patched in updates. Keep your apps updated.


FAQ: Document Security

How do I encrypt documents on my phone?

Use a document scanner app with built-in encryption like Scanify PDF. Documents are automatically encrypted when backed up to the cloud using AES-256 encryption.

Is Google Drive secure for sensitive documents?

Google Drive uses encryption in transit and at rest, but Google holds the encryption keys. For sensitive documents, use an app that encrypts files before uploading, like Scanify PDF.

What is AES-256 encryption?

AES-256 is a military-grade encryption standard. The “256” refers to the key size — there are more possible combinations than atoms in the observable universe. It’s virtually uncrackable with current technology.

Should I password-protect PDFs?

Yes, for documents you might share or that contain highly sensitive information. Password-protected PDFs add an extra layer even if the file is somehow accessed.

What happens if I forget my encryption password?

With true end-to-end encryption, there’s no way to recover data if you forget the password — that’s the point of security. Use a password manager to store complex passwords safely.

Is it safe to scan my passport?

Yes, if done correctly:

  1. Use an app with encryption (Scanify PDF)
  2. Enable app lock
  3. Password-protect the PDF
  4. Store only in encrypted backup

Having a digital copy can actually help if your physical passport is lost.


Your Security Checklist

Before storing sensitive documents on your phone:

  • Device lock enabled — Biometric + strong PIN
  • Document app with encryption — AES-256 or equivalent
  • App lock enabled — Extra protection for document app
  • Encrypted cloud backup — Documents encrypted before upload
  • Password-protected PDFs — For highly sensitive documents
  • Updated apps — Latest security patches installed
  • Permissions reviewed — No unnecessary app permissions

Get Started

Secure document storage doesn’t have to be complicated. Scanify PDF makes it easy:

  1. Download — Free on Android (iOS coming soon)
  2. Enable app lock — Add biometric protection
  3. Sign in to Google — Enable encrypted backup
  4. Scan documents — Automatic encryption happens behind the scenes

Your sensitive documents deserve enterprise-grade security. And now it’s free.


Questions about document security? Contact us at support@buildwize.app