A wireless device can store account identifiers and facilitate transactions. The wireless device can be loaded with user account identifiers and can be presented to various checkpoint devices. When presented, the wireless device can transmit a selected account identifier to the checkpoint device. In the context of a purchase transaction, the checkpoint device can be a point-of-sale terminal and the account data can be financial account data. In some instances, the wireless device can also facilitate a purchase transaction, e.g., by obtaining information about products to be purchased, constructing a purchase order from the product information, and transmitting the purchase order to a point-of-sale terminal.