Why writing your number on the dashboard is a 2010s habit

There's a number written on the dashboard of approximately 47 million Indian cars right now. It's been there for a decade. And for a decade, it has been quietly funding the country's spam-call industry.

It started as a courtesy. You'd park awkwardly somewhere, scribble your phone number on a piece of paper, slip it under the wiper. The next driver could call you to move. Polite. Civilised. Indian.

Then phones got cameras. Then they got OCR. Then they got bots. And what was once a private message between two strangers became a public broadcast to anyone who happened to walk past.

The math

An average parked car is photographed by 80–120 different people per week in a metro. If even one in fifty pictures is uploaded — to a "lost dog" group, a parking complaint forum, a WhatsApp gossip thread — your number is now in roughly three new datasets per week.

Multiply that by 52 weeks. Multiply that by the seven years you've owned the car. The number on your dashboard isn't on your dashboard anymore. It's on a hard drive in Delhi. And another one in Hyderabad. And one in Manila that you'll never know about.

The most efficient phishing operation in the country isn't an app. It isn't a leak. It's a pen and a piece of paper, sitting on 47 million dashboards.

The fix is embarrassingly simple

Don't put your number on the dashboard. Put a relay there. Anyone who needs to reach you, can. Anyone who wants to harvest you, can't. The QR is meaningless to a database — it's just a URL pointing to a service that knows how to find you.

This isn't a new idea. Email did this thirty years ago with reply-via-relay. SMS did it in 2014. Uber's done it for every ride since 2016. The only reason we never did it for cars is that nobody made a sticker.

What changes

• Strangers can still reach you. Instantly.
• Spammers can't enumerate, harvest, or resell.
• You can mute a sender once. They can never reach you again.
• Your phone number gets to be private again — the way it was supposed to be.

It took us about a year to build Vtag. It took us a decade of writing numbers on paper to admit we needed it. We hope yours is the last dashboard with a phone number on it.