Comparison

Underlayer vs Authenticator App₊

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

Head to head
About

Underlayer

Features
Read full description

UNDERLAYER - STEGANOGRAPHY MADE SIMPLE Transform ordinary images into secret carriers. Hide confidential messages invisibly within photos and share them through any messenger without raising suspicion. KEY FEATURES: HIDE SECRETS • Embed text messages invisibly into any image • Two encoding modes: Hidden (invisible pixels) and Open (colored frame) • Open mode survives messenger compression (Telegram, WhatsApp, etc.) • Share processed images directly or save to gallery REVEAL MESSAGES • Extract hidden text from steganographic images • Automatic detection of encoding method • Works with images received through messengers • Share intent support - open images directly from gallery WHY UNDERLAYER? • Simple & Intuitive - No cryptography knowledge required • Messenger-Friendly - Open mode designed for compressed sharing • Privacy First - All processing happens locally on your device • Universal - Works with JPG, PNG, WebP formats • No Account Required - Start using immediately USE CASES • Private communication through public channels • Watermarking images with hidden ownership data • Secure note-taking in plain sight • Educational tool for learning steganography • Fun way to send secret messages to friends SECURITY & PRIVACY • No internet connection required for processing • Your messages never leave your device • No data collection or tracking • Complete control over your secrets PREMIUM FEATURES • No banner ads at the bottom • No interstitial ad interruptions • Process unlimited images without ad breaks HOW IT WORKS 1. Select any image from your gallery 2. Enter your secret message 3. Choose encoding mode (Hidden or Open) 4. App embeds message into image pixels 5. Share through messengers or save locally 6. Recipient opens image in Underlayer to reveal message ENCODING MODES EXPLAINED HIDDEN MODE • Message embedded invisibly in image pixels • Completely undetectable to human eye • Best for uncompressed image sharing • Lost when image is compressed by messengers OPEN MODE • Message encoded as colored frame border • Visible as decorative edge around image • Survives Telegram, WhatsApp compression • Recommended for messenger sharing INTERNATIONAL • Available in English and Russian • More languages coming soon • Automatic language detection Whether you're a privacy enthusiast, security professional, or just curious about steganography - Underlayer makes it accessible to everyone. Download now and start hiding your secrets in plain sight! Terms of use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Authenticator App₊

This app generates secure, time-based one-time passwords (TOTP) for two-factor authentication (2FA) and multi-factor authentication (MFA). It supports QR code scanning and manual setup, works offline, and offers encrypted backups and iCloud sync across Apple devices.

Highlights
  • Secure 2FA & MFA code generation
  • QR code scanner and manual setup
  • Offline authentication codes
  • Encrypted backup and restore
  • iCloud sync across Apple devices
  • Face ID, Touch ID, or PIN lock
Features
Read full description

Authenticator App is a secure, simple and private 2FA authenticator for protecting your online accounts. Set up secure sign-in in seconds. Scan a QR code or enter your setup key manually, then use Authenticator App to create verification codes whenever you need to log in. Your 6-digit 2FA codes refresh automatically and work offline, so you can access your accounts even without internet or cellular connection. Generate two-factor authentication codes, multi-factor authentication tokens and time-based one-time passwords (TOTP/OTP) for Google, Microsoft, Facebook, Instagram, Twitter (X), LinkedIn, Amazon, Dropbox, PayPal, eBay, Snapchat, Pinterest, Reddit, Yahoo, Shopify, Slack, Zoom, Airbnb, Uber, and thousands of other apps and websites. WHY CHOOSE AUTHENTICATOR APP? • Secure 2FA & MFA Code Generator Store and generate one-time password codes for two-factor authentication, multi-factor authentication, 2-step verification and account login protection. • QR Code Scanner & Manual Setup Add accounts quickly by scanning a 2FA QR code or entering a secret key manually. Setup is fast, easy and beginner friendly. • TOTP & OTP Support Authenticator App supports time-based one-time passwords (TOTP), OTP software tokens and verification codes used by popular online services. • Encrypted Backup & Restore Keep an encrypted backup of your authentication tokens so you can restore your codes when you upgrade, replace or lose your device. • iCloud Sync Across Apple Devices Securely sync your 2FA codes across iPhone, iPad, Mac and Apple Watch for convenient access on all your Apple devices. • Face ID & Touch ID Lock or PIN Protect your authenticator codes with Face ID, Touch ID or device security for an extra layer of privacy. • Offline Authentication Codes Generate secure login codes without Wi-Fi, mobile data or network access. Your authenticator tokens remain available anywhere. • Works With Popular Services Use Authenticator App for Google, Microsoft, Facebook, Instagram, Amazon, Coinbase, Roblox, GitHub, LinkedIn, Discord, Dropbox, Twitter/X and many more services that support 2FA, MFA, TOTP or OTP codes. Authenticator App helps make account security easier. Add a second layer of protection to your email, social media, banking, crypto, shopping, gaming, work and personal accounts with secure two-factor authentication. Important: Authenticator App is an independent 2FA code generator and is not affiliated with Google, Microsoft, Facebook, Instagram, Amazon, Coinbase, Roblox or any other third-party service. The app works with services that support standard TOTP/OTP authentication. SUPPORT Need help or want to request a feature? Contact us: support@vunyo.com TERMS & PRIVACY Privacy Policy: https://vunyo.com/apps/authenticator/privacy Terms of Use: https://vunyo.com/apps/authenticator/terms SUBSCRIPTION TERMS • Payment will be charged to your iTunes Account once purchase is confirmed. • Subscriptions renew automatically unless auto-renew is switched off at least 24 hours before your current period ends. • Your account will be charged for renewal within 24 hours before the end of the current period. • Manage or cancel your subscription via your Account Settings. • If a trial is offered, the full subscription price will be charged when the trial period ends unless cancelled beforehand.

Screenshots

Underlayer4 screens
Authenticator App₊4 screens

Verdict

The call

The clearest difference is update cadence: Authenticator App₊ at every 5 weeks against Underlayer's every 5 months. 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. Underlayer sells 1 in-app purchase, starting at $2.99 per 7 days and Authenticator App₊ sells 2 in-app purchases, starting at $5.99 per 7 days. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Underlayer ships an update every 5 months, Authenticator App₊ every 5 weeks. The most recent releases landed on September 12, 2026 and September 18, 2026 respectively.

Scorecard1 real difference · 8 level
Underlayer versus Authenticator App₊: the parameters behind the verdict, then further details
ParameterUnderlayerAuthenticator App₊
PriceFreeFree
Rating5.0 (1 ratings) — better
Number of ratings1 — better
Update frequencyEvery 5 monthsEvery 5 weeks — better
AdsYesYes
In-app purchasesYesYes
MonetizationFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.115.1
Further details — not scored
Size169 MB73 MB
Age rating4+4+
DeveloperMihail RukavishnikovVUNYO BILGI TEKNOLOJILERI LIMITED SIRKETI

In-app purchases

1 purchases

Underlayer

Subscriptions1
  • Premium$2.997 Days
2 purchases

Authenticator App₊

Subscriptions2
  • Weekly Premium3 Days trial$5.997 Days
  • Yearly Premium$49.991 Year

Questions

Is Underlayer free?
Underlayer is free to download, with in-app purchases available.
Is Authenticator App₊ free?
Authenticator App₊ is free to download, with in-app purchases available.
Do Underlayer or Authenticator App₊ have ads?
Both Underlayer and Authenticator App₊ show ads.
Which is updated more often, Underlayer or Authenticator App₊?
Underlayer ships an update every 5 months, and Authenticator App₊ every 5 weeks. Most recently, Underlayer was updated on September 12, 2026 and Authenticator App₊ on September 18, 2026.

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