The survey of 394 IoT developers found that 33% currently develop IoT solutions, with over 50% learning about IoT. Hardware vendors and semiconductor manufacturers most influence technology selection. Top concerns are security, interoperability and hardware integration. 81% use open source. Popular technologies include HTTP, MQTT, Java, C, Linux. Intel, Google, Cisco, IBM and Bosch are seen as IoT leaders. The Eclipse IoT, IEEE and IETF consortiums are most important.