Systems and methods for implementing mobile payments. In an aspect of in-store purchase, a merchant sends a payment amount and merchant account info to transaction center. A buyer sends a code and buyer account info to transaction center. The code represents the merchant. In an aspect of online purchase, an e-commerce merchant provides options for a buyer to use names other than a first name plus a surname. In one embodiment, a buyer submits a shortened name or nickname for online purchases when a given payment service is used as a payment method.