Show HN: Payo – I got tired of losing contacts at conferences, so I built (opens in new tab)

I go to a lot of tech events and conferences. The pattern is always the same: have a great conversation, swap some details verbally, promise to follow up… and then lose half of it by the time I sit down. I tried everything scanning badges (when they exist), typing notes into my phone mid-conversation (awkward), taking photos of business cards (who carries those anymore). Nothing stuck. So I built Payo. It's a PWA no app store, just open it on your phone. The core flow: tap record, say what you remember about someone for 10 seconds, and Payo extracts a structured contact (name, company, email, phone) automatically. The whole thing is designed around one principle: if you're not getting value within 5 seconds of stopping the recording, you're not getting value. How it works under the hood:

Deepgram Nova-3 streams transcription in real-time via WebSocket (sub-300ms, words appear as you speak) If you're offline (because conference WiFi is always terrible), it falls back to local Whisper running in a Web Worker via WASM so it never freezes the UI Rule-based cleanup runs instantly (<50ms) to strip filler words and extract emails/phones from spoken text ("john at gmail dot com" → john@gmail.com) An optional cloud tier does LLM-powered cleanup if connectivity allows (3-second hard timeout, so it never blocks you)

The key insight: at events, you have maybe 30 seconds between conversations. You need something faster than opening the Contacts app and typing. A 10-second voice note that auto-parses into a contact card is that thing.

Stack: React + Vite + Supabase + Deepgram Nova-3 + Whisper WASM. It's a PWA with offline support, so it works even in airplane mode (Whisper handles transcription locally). I've been using it at events for a few months and it's changed how I network I actually follow up now because I have the context of why I wanted to connect, not just a name.

Would love feedback from anyone who goes to conferences regularly. What's your current system for capturing contacts?