US Patent 11488133 Add-on application for point of sale device

A point of sale application may initially process a transaction between a customer and a merchant. While the point of sale application processes the transaction, an add-on application may monitor a current state of a user interface of the point of sale application. Upon recognizing a triggering event associated with the current state of the user interface, the add-on application may take over the processing of the transaction from the point of sale application. Upon completion of the processing of the transaction, the add-on application may return a result of the transaction to the point of sale application by emulating user actions on the user interface of the point of sale application.