Systems and methods are disclosed to provide an animated 2D barcode check that is used to securely and efficiently transmit financial information between mobile devices. The financial information includes a check written by a payer and transmitted to a merchant. The check includes account information of the payer and of the merchant with a payment service provider, a payment amount, and a cryptographic signature that has been certified by the payment service provider. The payer's mobile device encodes the check into a sequence of 2D barcodes and displays the sequence of 2D barcodes in a loop that is scanned by a camera on the merchant's mobile device. The merchant uses the cryptographic signature to verify the validity of the signature on the check without having Internet connectivity to the payment service provider. The merchant may later present the check to the payment service provider to receive payment.