What is the fine-grained topic of the following text: The report states that “ Karl also spent 5 years working in China for Gemalto (and Trustonic) as liaison and evangelist of embedded Mobile Near-Field Communications Payments & TEE security technologies to the OEM Smartphone/Tablet PC ecosystem. Only return the topic.
Karl's work in China promoting Mobile Near-Field Communications Payments & TEE security technologies for Gemalto and Trustonic.