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Protection against grandparent scams & fake calls

Is that really your grandson on the phone?

Scammers call, claim to be a grandchild, a daughter, the police or the bank, and pile on the pressure. Certifon gives your family one simple rule: check the number first, then talk. It takes ten seconds and works with an ordinary landline phone too.

Set it up for free How does it work?

Free · No ads · No account needed · Large text, few buttons

Grandmother and grandson laughing on the phone, both phones show a green tick
The scam

How a scam call unfolds

The stories change, the pattern stays the same. Once you know it, you recognise it.

📞

A familiar voice, an emergency

“Grandma, it's me! I've had an accident and I need money right now.” Sometimes the voice even sounds real, because voices can be imitated by computers these days.

⏰

Time pressure and secrecy

“Please don't tell anyone, it has to happen fast.” That pressure exists precisely so you don't stop to think or ask someone.

🔢

The number proves nothing

Even if the display shows your daughter's number or the police: caller numbers can be faked. The display is a claim, not proof.

How to protect yourselves

A story in four pictures

Set up once over family coffee, then checked in seconds on every call.

Grandmother and grandson laughing at the kitchen table, holding their phones together
1

Connect once, in person

On the next visit, each of you briefly shows the other a code on your phone, like taking a photo. From then on the two devices know each other, and only those two. No stranger can sneak in later.

“We did that on Sunday in two minutes.”

Grandmother in an armchair with the landline handset at her ear, doubtful look, her smartphone lying next to it
2

The call comes

Weeks later the phone rings. “It's me, something's happened.” The number looks familiar, the voice sounds almost right. This is exactly when the family rule applies.

“Hold on, I'll ask you for the number first.”

Over the grandmother's shoulder: handset at her ear, on the table her smartphone with six empty boxes
3

“What number do you see?”

Both open Certifon. The caller reads the six-digit number from their phone, you type it into yours. The number changes every minute and comes only from your personal connection. No scammer can know it, however convincing they sound.

“The phone just sits next to the landline handset.”

Grandmother and grandson laughing on the phone, both phones show a green tick
4

Green: talk. Red: hang up.

If the number matches, Certifon shows a green tick and you can talk in peace. If it doesn't, the app tells you exactly what to do: hang up and call the person back on the number you already know.

“A real grandson doesn't mind waiting a moment.”

The family rule: whenever it's about money, passwords or urgency, check the number first.

Whoever knows the rule can't be rushed. And whoever means it honestly is happy to check along.

With a free account

The whole family stays connected

Checking works without any account. With one, it gets more convenient, and the kids can help.

Contacts on every device

New phone, added a tablet: your connected contacts are backed up encrypted and back within minutes. Nobody but you can read them, not even us.

Request a check

You call Grandma and tap “request verification” first. Her phone alerts her and the right screen is already open when she picks up. No hunting through menus.

Green on both sides

As soon as the number matches on one side, the other side gets the green tick too. Both of you know: that really was us.

Lost your phone? One tap

“I think my device is gone.” One tap, and every connected contact sees a warning sign until you've reconnected.

Sign in with a fingerprint

No password to remember: fingerprint or face is enough. If you'd rather have a password, you can use both.

Same language and look everywhere

German, English or French, light or dark: set it once, the same on every device.

If it doesn't match: three steps

  1. Hang up. No explanation, no guilt.
  2. Call back yourself, using the number in your own phone book.
  3. Tell someone. Family, neighbours, the police. Scammers rely on people staying quiet.

And most importantly: a real grandson, a real bank and the real police never mind you checking first.

For relatives

How to set it up for Grandma or Grandpa

Ten minutes on your next visit. After that it runs by itself.

  • 1
    Open Certifon on both phones. No app store install needed: open the page in the browser and choose “Add to home screen”.
  • 2
    Connect once. “Connect a new contact”, each scans the other's code. Done.
  • 3
    Talk through the rule. Money, passwords or urgency: number first, then the conversation. Best to leave a note next to the phone.
  • 4
    Optionally create an account so the contacts survive a new phone and you can use “request verification”.

Frequently asked questions

Does Grandma need a smartphone?

Yes, one is needed, but it doesn't have to be her phone. It simply lies next to the landline handset and shows the number. An inexpensive, older device is fine.

Does Certifon cost anything?

No. Checking is free and stays free. The account is free as well.

What if the caller doesn't have Certifon?

Then the old rule applies: hang up and call back on the known number. Certifon doesn't replace common sense, it just makes it easier.

Does Certifon see who we call?

No. The check happens only between your two devices. If you create an account, your contact list is backed up encrypted so that only you can read it.

Is this for companies or clubs too?

For that there's the product page for organisations with the technical details.

At the next family coffee: two minutes that save a lot of trouble

Certifon runs in the browser on any phone. Free, no ads, no account.

Open Certifon