Part of KnytX Shield — included from Basic, with the Scam Vulnerability Score added on Pro and above.

Call and link defence

Scam call coming in?

You already know.
Block scam calls and phishing texts before you tap. A verdict banner on every inbound call, plus early scam-call warnings on Pro. No invasive permissions.
Join the waitlist · launching soon
~1s
Call-time verdict (typical)
Basic+
Passive layer included
Pro
Preemptive layer included
0
Invasive permissions

One passive layer. One preemptive layer.

Passive Call Shield

Inbound calls get a verdict against the verified-org directory and fraud-reputation feed before the second ring — a banner, never a permission prompt.

Passive Link Shield

Phishing links in texts get flagged before you tap. Even a message that quotes your card’s last four digits gets checked — real details don’t make a fake link safe.

Preemptive scam warnings

Pro tier. When a known scam campaign matches your exposure pattern, you get a heads-up before the call arrives. Hours of warning, not seconds.

Scam Vulnerability Score

Pro tier. A composite signal of which scam pretexts you’re most likely to fall for, based on exposure and breach history. Not a credit score.

Verified-org directory

Banks, government departments, and schools register their outbound numbers — when they call, the verdict is positive and named. Most scam calls die right there.

Family Auto-Shield routing

On the Family plan, a flagged call to a member in elderly mode routes a notification to the plan owner — in time to intervene.

From inbound call to scam-call alert.

1
Call rings
An inbound call hits your phone. The background service checks the number against the verified-org directory and the fraud-reputation feed, typically in about a second.
~1s verdict
2
Banner appears
A small banner above the incoming-call screen states the verdict: verified business, spam likely, scam likely, or unknown. You decide — the phone doesn’t auto-reject.
Banner, not auto-reject
3
Log and learn
Every flagged call feeds back into your Scam Vulnerability Score. Pro uses this signal to send preemptive warnings about active campaigns matching your exposure.
Feedback loop, weekly digest

How Scam Shield blocks scam calls without auto-reject

Two layers: a passive verdict at the moment of the call, and a preemptive warning hours ahead. Basic includes passive; Pro includes both.

Scam Shield is two products under one banner. The passive layer runs at the moment of the call or message. It checks the number against the verified-organisation directory and the known-fraud feed, shows a small banner above the dialler or SMS preview, and leaves the decision to you.

The preemptive layer runs hours or days ahead: when a known scam campaign matches your exposure pattern, you get a warning before the first call lands. Basic includes passive. Pro includes both.

Why no auto-reject

A one-second verdict is good enough to inform your decision. It isn’t good enough to auto-block without losing legitimate calls, so the default is a banner, not a block. If you do want a hard block, the dashboard supports a per-category policy: verified-business never blocked, scam-likely auto-rejected, unknown set to require a callback.

What “preemptive” actually means

When a scam campaign starts running a pretext aimed at your breach profile, you get a heads-up before the text arrives — hours, not seconds.

The breach-to-scam correlation engine sits on top of your exposure data. When a scam campaign starts running a pretext aimed at the group your breach pattern places you in, you get a heads-up before the text reaches your phone. One example: recent shoppers from a known retailer breach, when a matching refund scam starts running. Twelve hours of warning beats twelve seconds, and twelve hours is what the preemptive layer typically buys.

The Scam Vulnerability Score in plain language

A single score for how vulnerable you are to active scams. The useful part is the breakdown: which pretexts, and what to change first.

The Score is a composite of your exposure pattern, your breach history, and the scam campaigns running in your jurisdiction. A score of 78 means you’re more vulnerable than 78% of people near you. The useful part isn’t the number — it’s the breakdown beneath it. For example: top-decile vulnerable to parcel-delivery pretexts, because three of your emails turned up in last quarter’s stealer-log dumps. The recommended actions list what to change first.

What it doesn’t replace

Scam Shield is the layer between you and the call. It isn’t a replacement for getting your data off the broker market. The call only knows your name because somebody sold it to the campaign. Pair Scam Shield with broker removal under KnytX Shield, and call volume typically drops, because scam campaigns struggle to find your number.

See also

Plan details
Available on Basic · Pro · Family · Team · Executive
Passive layer All paid tiers
Preemptive layer Pro and above
Platforms iOS · Android · F-Droid
Hosting Our own servers
Status Waitlist · launching soon

Choose your tier

Basic
Passive call and link defence — sub-second verdict, no app foreground.
$8.99/per month
  • Passive Call Shield (scam-number verdicts on inbound calls)
  • Passive Link Shield (SMS phishing detection)
  • Verified-org directory lookup
  • Banner verdicts — no auto-reject
  • Runs on iOS and Android, no accessibility permissions
Join the waitlist — Basic →

Who it's for

Adult children worried about elderly parents

Pair with the Family plan and Family Auto-Shield routes scam-call notifications to you — the intervention point before a parent calls back.

Anyone tired of being asked about their car's extended warranty

Robocalls and spam ID are table stakes. Passive Call Shield catches the scam layer beneath: calls that look local and ask for an OTP.

Recent shoppers and recent tax filers

Parcel-delivery and tax-refund pretexts are among today’s highest-volume scam categories (per FTC reporting), both keyed to your recent activity. Preemptive warnings flag the campaign first.

People who can't read another bank-impersonation text

If you’ve stopped reading bank texts because you can’t tell which is real, Scam Shield helps. The banner tells you before you read it.

Frequently asked questions

Does Scam Shield require accessibility permissions or a foreground app? #
No. We use the built-in call- and message-screening hooks Apple and Google provide — no accessibility access, no foreground app. On iOS that’s CallKit and a Messages filter extension; on Android it’s CallScreeningService and a system message filter. No accessibility prompt, no invasive permissions.
What's the difference between passive and preemptive? #
Passive runs at the moment of the call or message: a verdict in about a second, a banner, your decision. Preemptive runs hours or days ahead, warning you when a known scam campaign matches your exposure pattern. Basic includes passive; Pro includes both.
How accurate is the verdict? #
The verified-org directory is high-precision by design: a verified-business banner is rarely wrong, because the organisation registered the number itself. The scam-likely banner is medium-precision and improves as users mark calls. We surface the verdict and let you decide rather than auto-rejecting, because false positives on auto-reject would cost you real calls.
Does this work for WhatsApp calls and Telegram calls? #
Passive Call Shield works on the system call layer (iOS and Android native dialler). VoIP calls through WhatsApp, Telegram, or Signal are out of scope for the passive call layer. The link layer does evaluate links sent over WhatsApp on Android. We’re working on broader VoIP coverage.
Will you store my call history? #
We don’t log your call history. The number-to-verdict lookup runs against an indexed reputation feed. Flagged calls contribute an aggregate signal to your Scam Vulnerability Score, and their number data is deleted within 30 days.
Why not just block the calls automatically? #
Auto-block on a sub-second verdict produces false negatives the user never sees and false positives the user never debugs. A banner respects your judgement and the underlying data. If you want a hard block, you can configure it per category — verified-business never blocked, scam-likely auto-rejected — from your dashboard.

Your phone should already know which call is a scam.

Passive Call Shield and Passive Link Shield run silently. No app foreground. No invasive permissions.

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