KnockKnock - Family Check-in

A simple knock to check in on the people you care about.

【Hardware-Secured Identity】
Every response is signed by a cryptographic key stored in your device's secure hardware chip.

【One Tap, Instant Peace of Mind】
Worried about a parent who lives alone? Send a knock. If they tap back, they're okay. If they don't, you know to check in another way.
No calls, no typing — just a tap.

【Built for Families】
Create a group for your family or close circle. Invite members with a QR code — it takes seconds. Up to 6 people per group.

【Simple Mode】
A single large button designed for anyone who finds smartphones overwhelming. Perfect for elderly parents or grandparents.

Joining a group is free.
Creating a group requires a one-time purchase.