Payment

1️⃣ Supported Payment Methods

• Unifi Apps must provide both fiat and crypto payment options on the product purchase screen, with each payment button offered separately.

A. Payment Support Overview

Version	Payment	Region
LINE MINI App	IAP Payments	Japan Only
LINE Login LIFF	Crypto & Stripe (Fiat) payments	Global
Web	Crypto & Stripe (Fiat) payments	Global

B. Fiat Payments via IAP (Coming Soon)

In-app billing through LINE App Platform

C. Fiat Payments via Stripe

Global payment processing handled by Stripe

Supported Payment Methods

• Credit / Debit Cards (VISA, Mastercard, AMEX, JCB, etc.)

• Apple Pay

• Google Pay

• Naver Pay (KRW only)

• Kakao Pay (KRW only)

Payment Method Rules

• Payment methods automatically adjust depending on:

  • The device OS (iOS / Android)

  • The selected payment currency (USD / Local currencies)

• Available methods may change based on Stripe policies

D. Crypto Payments

Supported cryptocurrencies

• KAIA

• USDT

2️⃣ Supported Currencies & Minimum Charge Limits

Type	Currency	Decimal(Max)	Charge(Max)	Charge(Min)
Fiat	USD	2	999,999	0.50
	KRW	0	999,999	750
	JPY	0	999,999	80
	TWD(NTD)	2	999,999	17
	THB	2	999,999	18
Crypto	KAIA	4	999,999	0.01
	USDT	2	999,999	0.01

📌 Optional Local Currencies Unifi Apps may optionally support additional local currencies depending on the user's region:

• JPY, TWD, THB, KRW

📌 Default Pricing Currency

• USD must be used as the primary pricing reference

3️⃣ Price Display Requirements

All product prices in Unifi Apps must be displayed to users in:

• A fiat currency

• A cryptocurrency (KAIA or USDT)

📌 Purpose of dual price presentation

• Provide a stable purchasing experience

• Prevent confusion from crypto price volatility

4️⃣ Payment Request Rules (Developer Input Requirements)

When user selects	Merchant must input price as
Fiat Payment via Stripe	A fixed USD-based amount
Crypto Payment	A fixed amount based on KAIA or USDT

📌 The currency conversion between USD and KAIA/USDT must be implemented and provided by the Unifi Apps.

5️⃣ User Notification Requirements

Unifi Apps must provide clear and real-time feedback to users about payment status.

Notifications must be:

• Immediate

• Clear

• Intuitive

• Prevent confusion such as double payments or uncertainty about success

Event	Description	Information to notify users (Example)
Successful purchase	Fiat/Crypto payment successful and item delivered	Successful purchase
Purchase failed/canceled	User requested to process Fiat/Crypto payment but payment failed	Purchase failed
	User clicked the "Back" button on the Fiat/Crypto payment screen or exited the screen	Purchase canceled
	User clicks the Decline Signature button on the Crypto payment screen	Purchase canceled
	User's Crypto balance is insufficient	Insufficient balance
	Other errors	Please try again later

6️⃣ Payment History

Unifi Apps must provide a UI that allows users to check their payment history. Refer to Unifi Apps SDK documentation for integration methods.