Available on Enterprise

Mobile Silent Auth - verify users without OTP

Mobile Silent Auth uses Silent Network Authentication (SNA) to verify a user's phone number directly through the mobile carrier network in under 5 seconds - no SMS code, no user interaction, no passwords. When the carrier network is unavailable, MojoAuth automatically falls back to OTP, so every user can still verify.

Verify phone numbers without making users type a code - on the same API as passkeys, magic links, OTP and social login. Available on Enterprise.

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Mobile silent authentication - carrier-level phone verification

Why OTP alone is not enough

SMS OTP has been the standard for phone verification - but it comes with real costs and security gaps that silent authentication eliminates.

OTP delivery delays

Silent auth resolves in under 5 seconds, invisibly.

SIM-swap & SS7 attacks

Carrier-level SIM checks mean there is no SMS code to intercept.

SMS phishing & social engineering

No code to phish - verification happens at the network level.

Per-message SMS costs at scale

Eliminate $0.01-$0.05 per OTP - silent auth is cheaper at volume.

User drop-off during OTP entry

20-30% higher completion rates with zero-interaction verification.

No verification on Wi-Fi

Full coverage via automatic OTP fallback on any network.

How mobile silent authentication works

A single API call triggers a carrier-grade identity check - no user action required.

User initiates verification
The user taps a verify button or triggers an auth flow. Their phone number is passed to the MojoAuth API.
Carrier network check
MojoAuth routes a check through the mobile data connection. The carrier verifies the SIM identity tied to that phone number in real time.
Match confirmed
The carrier returns a cryptographic match/no-match response. No personal data is shared - only a boolean verification result.
Fallback if needed
If the user is on Wi-Fi, VPN, or an unsupported carrier, MojoAuth instantly falls back to SMS or email OTP - seamlessly, without the user noticing a gap.

How mobile silent authentication works - carrier verification flow

Full coverage via automatic OTP fallback

Silent auth works when users are on mobile data. When it can't, MojoAuth handles the fallback automatically.

On mobile data

Silent authentication is attempted first. The carrier verifies the SIM identity directly - no code sent, no user interaction, verification in under 5 seconds. This is the primary path for the majority of mobile users.

On Wi-Fi, VPN, or unsupported carrier

MojoAuth detects that silent auth is unavailable and automatically triggers SMS or email OTP - within the same API call. The user experience remains seamless. No developer logic needed to handle the switch.

One integration. Two verification paths. Zero gaps in coverage.

Key features

Enterprise-grade silent verification with carrier-level security

SIM-swap protection

Real-time carrier check detects recently swapped SIMs. If the SIM doesn't match the phone number, verification fails - stopping account takeover before it starts.

Zero-friction verification

No codes to type, no apps to switch to, no waiting. Users tap once and verification happens invisibly in the background. 20-30% higher completion rates vs. OTP.

Global carrier coverage

Connected to mobile network operators across 30+ countries - covering major carriers in North America, Europe, Asia-Pacific, Latin America, and Africa.

Privacy-first design

No personal data is transferred. The carrier returns only a match/no-match result. Fully compatible with GDPR, CCPA, and data residency requirements.

Sub-5-second resolution

The entire carrier verification round-trip completes in 2-5 seconds. Compare that to 15-60+ seconds for SMS OTP delivery and manual entry.

Automatic OTP fallback

When silent auth isn't possible (Wi-Fi, VPN, unsupported carrier), MojoAuth falls back to SMS or email OTP - automatically, within the same API call.

One API call. Two verification paths.

Integrate silent authentication with automatic OTP fallback in a single implementation. MojoAuth handles carrier detection, network routing, and fallback logic - your code stays simple.

Silent auth attempted first, OTP fallback automatic
Single callback for both verification paths
Real-time status and analytics dashboard

View integration guide

app.js

const mojoauth = new MojoAuth("YOUR_API_KEY", {
  redirect_url: "https://yourapp.com/callback",
  source: [
    { type: "phone", feature: "silent_auth" },
    { type: "phone", feature: "otp" } // automatic fallback
  ]
});

// Silent auth is attempted first.
// If unavailable (Wi-Fi, VPN, unsupported carrier),
// OTP is triggered automatically - same callback.

mojoauth.signIn().then(response => {
  console.log("Verified:", response);
  // response.method: "silent_auth" | "otp"
  // response.phone: "+1234567890"
  // response.access_token: "eyJ..."
}).catch(error => {
  console.error("Verification failed:", error);
});const mojoauth = new MojoAuth("YOUR_API_KEY", {
  redirect_url: "https://yourapp.com/callback",
  source: [
    { type: "phone", feature: "silent_auth" },
    { type: "phone", feature: "otp" } // automatic fallback
  ]
});

// Silent auth is attempted first.
// If unavailable (Wi-Fi, VPN, unsupported carrier),
// OTP is triggered automatically - same callback.

mojoauth.signIn().then(response => {
  console.log("Verified:", response);
  // response.method: "silent_auth" | "otp"
  // response.phone: "+1234567890"
  // response.access_token: "eyJ..."
}).catch(error => {
  console.error("Verification failed:", error);
});

Built for industries where phone verification matters most

Silent authentication is ideal wherever mobile phone numbers serve as a trust anchor - onboarding, transactions, and account security.

Fintech & banking

Verify customer identity during account opening, loan applications, and high-value transactions. SIM-swap protection prevents unauthorized access to financial accounts.

E-commerce & marketplaces

Reduce fake account creation and verify buyers and sellers at signup. Faster checkout flows with silent re-authentication on returning visits.

Ride-sharing & gig economy

Onboard drivers and riders with instant phone verification. Re-authenticate users silently before each trip for safety and compliance.

OTT & streaming platforms

Prevent account sharing and verify device ownership. Silent auth ties subscriptions to verified phone numbers without interrupting the viewing experience.

Healthcare & insurance

Meet identity verification requirements for patient portals and claims processing. HIPAA-ready (BAA on Enterprise), with no patient-side friction.

SaaS apps

Add silent phone verification as a factor in your MFA flow. Protect high-value user accounts without adding friction.

Silent auth vs. traditional OTP

Side-by-side comparison of verification methods

Comparison of mobile silent authentication (with automatic OTP fallback) versus traditional SMS OTP across verification time, user interaction, SIM-swap protection, phishing risk, completion rate, cost, Wi-Fi support, and coverage.
Feature	Silent Auth + OTP Fallback	SMS OTP Only
Verification time	2-5 seconds	15-60+ seconds
User interaction	None (single tap)	Read SMS, type code
SIM-swap protection	Yes - carrier-level check	No
Phishing risk	None - no code to intercept	High - codes can be phished
Completion rate	20-30% higher	Baseline
Per-verification cost	Lower at scale	$0.01-$0.05 per SMS
Works on Wi-Fi	Falls back to OTP	Yes
Coverage	Full coverage via automatic OTP fallback	Depends on SMS delivery

Verify mobile users instantly - no OTP required

Mobile Silent Auth is available on Enterprise. Book a demo to see silent verification with automatic OTP fallback.