Show HN: LeaveNote – A privacy-focused instant messaging QR code application (leavenote.me)

Hi HN

I built LeaveNote because I kept running into the same real-world problem:

I wanted to be reachable when I wasn’t around — but I didn’t want to put my phone number or email on my door, car, or mailbox.

LeaveNote lets you create a simple QR code that strangers can scan to send you a message instantly, without seeing any of your personal contact details.

Typical use cases: • Door notes (“I stopped by, please contact me”) • Parking issues (“Your car is blocking the exit”) • Package delivery messages • Lost & found (pets, items) • Short-term contact without exchanging numbers

How it works: 1. You create a note template (door / parking / delivery / custom) 2. LeaveNote generates a unique QR code 3. A stranger scans it and sends a message 4. You receive the message via Telegram (more channels later) 5. Messages are forwarded instantly and not stored

Design principles: • No phone numbers or emails exposed • No account required for the sender • Minimal UI, works on any device • Built for offline, real-world scenarios

The project is currently free to use. I’m sharing it early to get feedback from the HN community: • Does this solve a real problem for you? • Are there scenarios I missed? • Any privacy or UX concerns?

Demo: https://leavenote.me

Happy to answer any questions or discuss the design decisions.