Max, undisclosed amounts means that they were small amounts and probably did not even return the investors their money back. It usually means that they could not find additional investment money, or another term often used is fire-sale.
What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.