In-Person QR Code Payments

KAELUM's QR code payment system allows you to accept and make payments in person, without needing cash or card terminals. Simply show your QR code or scan someone else's to transfer KAELUM instantly.

How It Works

Every KAELUM account has two QR payment features:

• My QR Code: Your personal QR code for receiving payments
• Scan to Pay: Camera scanner to pay others by scanning their QR code

All transfer types are supported:

• User → User (peer-to-peer)
• User → Merchant (customer payment)
• Merchant → User (refund or payment)
• Merchant → Merchant (B2B payment)

Using Your QR Code (Receiving Payments)

Access Your QR Code

Go to Wallet → My QR Code. You'll see your personal QR code along with your name and account details.

Static vs Dynamic QR Codes

Static QR Code (Default):

• No preset amount - payer enters the amount
• Long-lived and reusable
• Perfect for general purpose receiving
• Can be printed and displayed permanently

Dynamic QR Code:

• Includes a specific amount
• Optional: Lock the amount so payer cannot edit
• Expires in 30 minutes
• Perfect for specific transactions

To create a dynamic QR code:

1. Click "Set Amount"
2. Enter the amount in KAE
3. Add an optional memo (e.g., "Coffee purchase")
4. Toggle "Lock amount" if payer shouldn't be able to change it
5. Click "Generate QR"

Displaying Your QR Code

Mobile Display:

• Show your screen to the payer
• They scan it with their KAELUM app
• Payment completes instantly

Fullscreen Mode:

• Click "Fullscreen" for a larger QR code
• Perfect for showing across a counter or at a distance
• Displays your name prominently

Print Display:

• Click "Download" to save as SVG
• Print and display at your shop counter, booth, or venue
• Customers can scan anytime

Sharing Your Payment Link

Click "Copy Link" to get a shareable payment URL. You can:

• Send via text message or WhatsApp
• Share in email
• Post on social media
• Add to your website

When someone clicks the link, they'll be directed to make a payment to you.

Scanning to Pay

Camera Scan Method

1. Go to Wallet → Scan to Pay
2. Allow camera access when prompted
3. Point your camera at the receiver's QR code
4. The code scans automatically
5. Review and confirm the payment

Manual Entry Method

If you can't scan (poor lighting, damaged code, etc.):

1. Click "Enter Manually"
2. Paste the payment link or enter the username
3. Click "Continue"
4. Enter amount and confirm

Payment Confirmation Screen

Before completing any payment, you'll see:

• Receiver Details: Name, username, account type
• Verified Badge: Merchants have a verified checkmark
• Amount: Editable unless locked by receiver
• Platform Fee: 4.5% fee (shown separately)
• Total: Amount + fee
• Memo: Optional note

Review carefully and click "Confirm Payment".

2FA Authentication

For large transfers (≥100 KAE), you may be prompted for additional authentication:

• PIN code
• Biometric (fingerprint/Face ID)
• 2FA code (if enabled)

Payment Receipt

After successful payment:

• You receive an instant receipt
• Transaction appears in your history
• Both parties receive notifications
• You can share or download the receipt

Security Features

QR Code Rotation

For extra security, you can rotate your static QR code:

1. Open My QR Code
2. Click "Rotate Code"
3. Confirm the action
4. Old QR code becomes invalid
5. New QR code generated

Use this if:

• You suspect your QR was compromised
• You shared it publicly and want to revoke access
• You want periodic security updates

Signature Verification

Every QR code includes a cryptographic signature that:

• Prevents tampering
• Validates authenticity
• Protects against fraud

Modified or fake QR codes are automatically rejected.

Expiration

Dynamic QR codes expire after 30 minutes to prevent:

• Stale payment requests
• Price manipulation
• Replay attacks

Fees & Limits

Transaction Fee

All in-person QR transfers have a 4.5% platform fee:

• Consistent across all transfer types
• Deducted from sender's balance
• Shown clearly before confirmation
• Covers payment processing and security

Example: If you send 100 KAE:

• Receiver gets: 100 KAE
• Fee: 4.50 KAE
• Total deducted from you: 104.50 KAE

Transfer Limits

Daily limits apply based on your account level:

• Bronze: 500 KAE per day
• Silver: 2,000 KAE per day
• Gold: 5,000 KAE per day
• Platinum: 10,000 KAE per day
• Merchant: Custom limits

Per-transaction maximum: 1,000 KAE (can be increased by contacting support)

Use Cases

For Personal Users

• Splitting bills: Dinner with friends, shared expenses
• Lending money: Repay friends instantly
• Buying from peers: Marketplace purchases
• Tipping: Service providers, content creators
• Gifts: Send KAELUM as a gift

For Merchants

• Point of sale: Counter payments without card terminal
• Pop-up shops: Mobile payment solution
• Events & markets: Quick checkout at booths
• Delivery payments: Cash on delivery alternative
• Service payments: Consultations, repairs, services

For Events

• Festival/concert vendors
• Charity fundraising
• Ticket sales
• Merchandise booths

Best Practices

As a Receiver

• Use dynamic QR codes for fixed-price items
• Display your QR prominently and at eye level
• Ensure good lighting for scanning
• Have a backup payment method available
• Check your transaction history regularly

As a Payer

• Verify the receiver's name before confirming
• Look for the verified badge on merchant accounts
• Double-check the amount before sending
• Add memos to help track your spending
• Save receipts for important transactions

Security Tips

• Never share your QR code with untrusted parties
• Rotate your static QR periodically
• Enable 2FA for large transfers
• Keep your app updated
• Report suspicious activity immediately

Troubleshooting

QR Code Won't Scan

• Ensure sufficient lighting
• Hold camera steady
• Try manual entry instead
• Clean your camera lens
• Update your app

Payment Failed

• Check your balance (amount + 4.5% fee)
• Verify you're within daily limits
• Ensure receiver's account is active
• Try again in a few moments
• Contact support if persists

Camera Permission Denied

• Go to device Settings → Apps → KAELUM
• Enable Camera permission
• Restart the app
• Use manual entry as alternative

FAQs

Is my QR code unique?

Yes, every account has a unique QR code linked only to you. Even if you rotate it, the new code is still unique.

Can I use my QR code on multiple devices?

Yes! Your QR code is tied to your account, not your device. You can display it on any device where you're logged in.

What happens if someone screenshots my QR?

They can only pay you, not access your account. However, if you're concerned, you can rotate your QR code to invalidate the old one.

Can I receive payments while offline?

No, both parties need internet connection. The payment happens instantly when scanned.

Are there refunds for QR payments?

The receiver can initiate a refund from their transaction history. Contact them if you need a refund.

Can I scan a QR code from a photo?

Yes! The scanner works with photos, screenshots, and printed codes.

Getting Help

If you need assistance:

• K-Ai Chat: In-app assistant for instant help
• Help Center: Search our knowledge base
• Support: Email support@kaelum.app
• Phone: Available for urgent issues