Anti-Fraud System

DropIn uses multiple layers of protection to ensure only real attendees can check in.

The Problem

Without protection, someone could:

1. Screenshot the QR code

2. Share it online (Twitter, Telegram, Discord)

3. Hundreds of people check in remotely

4. Giveaway is ruined - actual attendees lose

The Solution

DropIn implements a multi-layer verification system.

Layer 1: Rotating QR Codes

The QR code displayed at venues changes every 30 seconds.

• Screenshots become invalid within 30 seconds

• By the time a shared QR spreads, it's expired

• Only people looking at the live screen can scan

Layer 2: Token Validation

Every check-in requires a valid session token.

• Tokens are single-use

• Tokens expire after 30 seconds

• Replaying old tokens fails validation

Layer 3: One Wallet Per Event

Each wallet address can only check in once per event.

• Prevents same person checking in multiple times

• Blocks wallet farming

• Ensures fair giveaway distribution

Layer 4: Event Locking

No check-ins allowed after giveaway draw starts.

• Prevents last-second gaming

• Draw pool is frozen at draw time

• Results are final and verifiable

Summary

Layer	Method	Protects Against
Rotating QR	30-second refresh	Screenshot sharing
Token Validation	Cryptographic tokens	Replay attacks
One Wallet	Address deduplication	Sybil attacks
Event Locking	Freeze at draw time	Late gaming