With the latest wolfMQTT v1.1 release you can easily connect your devices running wolfMQTT to IBM’s Watson IoT Platform. Trying out wolfMQTT is simple using the provided MQTT client example and your IBM Cloud account. The default example provides a link to the IBM Quickstart broker where you can view a graph generated by the data without an account.
As a side note, wolfMQTT uses the wolfSSL embedded SSL/TLS library for SSL/TLS support. Since wolfSSL supports TLS 1.3, your wolfMQTT-based projects can now use MQTT with TLS 1.3 with a supported broker!