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Profile Tap

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I built a QR-code safety tag for my kid’s school bag — the privacy problem became the interesting part

My 7-year-old started school this year and still doesn’t remember my phone number by heart.

The school suggested putting a contact sticker on the bag, but that meant my personal number was visible to literally anyone handling the bag during pickup, transport, or playtime.

That felt like a weird privacy tradeoff.

So over a weekend I built a tiny QR-based “family safety profile” system for him.

The architecture ended up being more interesting than I expected.

The setup:

One profile per family member
First name only
Emergency contacts
Safe-to-share medical details (blood group, allergies)
One-tap “I found this child” action
Mobile-first web profile that opens without installing an app

The hardest part was contact privacy.

If a random adult scans the QR, they should be able to reach the parent instantly — but they should NOT see the parent’s personal number.

I solved this using a routed communication layer with WhatsApp Business APIs and masked contact forwarding.

That design choice changed the whole product.

A lot of existing emergency-tag products expose raw phone numbers directly. In India, that quickly turns into spam and privacy issues.

The hardware side was intentionally simple:

Laminated PVC tag
Riveted onto the school bag strap
Waterproof enough for monsoon + daily school abuse

A few friends asked if they could use the same setup for:

autistic children
elderly parents with dementia
pets
kids commuting alone

That eventually turned into a small side project called ProfileTap Family Safety Profiles.

The biggest technical lesson for me:
privacy primitives are not “extra features” in India — they are the product.

Curious if anyone else here has shipped a tiny side project that unexpectedly became useful in the real world.

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