n recent years, "IoT" or "Wearable" are one of buzzwords, so you might have interests in building hardware products. But learning how to develop electric circuits, mechanical systems or embedded systems etc. from zero is so difficult.
However, iOS developers can contribute to projects of hardware products with the knowledge of Core Bluetooth / Bluetooth Low Energy (BLE), even if they are not familiar with hardware layer.
In this session, you can learn the basics of Core Bluetooth / BLE (what it is, why we use it, and how it works), and practical knowledges to build apps for hardware products (how to design the apps, how to test without actual hardware prototypes, troubleshooting tips, and how the apps can be reviewed by Apple) which I learned through actual IoT/Wearable projects.
This would be interesting & understandable even if you are not familiar with or have no interests in Core Bluetooth because of the actual examples.