Near-Field Communication (NFC) is a widely adopted standard for embedded low-power devices in very close proximity. In order to ensure a correct system, it has to comply to the ISO/IEC 14443 standard. This paper concentrates on the low-level part of the protocol (ISO/IEC 14443-3) and presents a method and a practical implementation that complements traditional conformance testing. We infer a Mealy state machine of the system-under-test using active automata learning. This automaton is checked for bisimulation with a specification automaton modelled after the standard, which provides a strong verdict of conformance or non-conformance. As a by-product, we share some observations of the performance of different learning algorithms and calibrations in the specific setting of ISO/IEC 14443-3, which is the difficulty to learn models of system that a) consist of two very similar structures and b) very frequently give no answer (i.e. a timeout as an output).