Secure transactions with offline device

Abstract

A method being implemented via execution of computing instructions configured to run at one or more processors and stored at one or more non-transitory computer-readable media. The method can include receiving a transaction amount and a preauthorization code from a first entity. The preauthorization code can include a preauthorization amount, an expiration time, and a digital signature. The transaction amount is for a transaction authorized by a user of a mobile device at a point-of-sale terminal of the first entity. The transaction amount is less than or equal to the preauthorization amount. The mobile device received the preauthorization code and stored the preauthorization code in the mobile device while the mobile device was in data communication with a mobile wallet provider. The mobile device provided a transaction code to the point-of-sale terminal while the mobile device was unable to communicate with the mobile wallet provider. The transaction code includes the preauthorization code, a transaction identifier for the transaction, and the transaction amount. The method also can include verifying the preauthorization code using the digital signature of the preauthorization code. The method additionally can include sending an approval for the transaction to the first entity in real-time while the user remains at the point-of-sale terminal of the first entity. Other embodiments are described.