Communication to the local mPress SDK is performed by calling the methods and properties made available to the mobile application by the mPress SDK library. Methods take JSON formatted strings as input and respond with JSON formatted strings. Note that these are JSON formatted strings and not actual JSON objects; this has been done intentionally to enable the use of the same implementations across many different languages and operating systems.
For information on JSON, including links on using it within different languages, see http://json.org/
| Method Name | RA1 | MPI |
| Initialize | N | Y |
| setBINList | N | Y |
| queryDeviceStatus | N | Y |
| startTransaction | Y | Y |
| completeTransaction | Y | Y |
| reprintTransaction | N | Y |
| resetDeviceStatus | Y | Y |
| getCustomerReceipt | N | Y |
| getMerchantReceipt | N | Y |
| getNumericData | Y | N |
| getMonetaryAmount | Y | N |
| enterKeyPressed | Y | N |
| chooseOption | Y | N |
| chooseYesNo | Y | N |
| stopTransaction | Y | N |
| queryDeviceInfo | Y | N |
| getDeviceInfo | Y | N |
| getCurrentAction | Y | N |
| getCardInsertionStatus | Y | N |
| configureDevice | Y | N |