Computing technology is becoming so flexible and ubiquitous that it can be incorporated into relatively mundane objects and devices. This enables tangible and embodied interaction with a large variety of artifacts, in a wide range of contexts, with a potentially large interaction space open for exploration. The availability and flexibility of these computationally enhanced objects also puts them in the hands of users who have significant domain skills and knowledge, but not necessarily the experience to fully utilize their interactive features.

The authors identify five key challenges for a certain type of users of such objects, referred to as end-user developers (EUDs). These EUDs are attempting to develop interactive experiences not for themselves, but for other users they encounter in their professional capabilities. The two specific examples addressed are educators and physiotherapists. While I agree that these challenges exist, I am not entirely convinced about their relevance and uniqueness for this particular context. One challenge is that the extensive amount of time it takes EUDs to modify a device outweighs the benefits of its initial purpose. Time is a necessary and fluctuating factor in the learning process, for all kinds of devices or activities. For example, setting up an exercise machine for a specific client may require initial training for the practitioner, and involves setup time before the client can use it. This is a reflection of the complexity of the device and the actions to be performed, and will happen with computer-based or mechanical systems.

The challenges the authors present largely focus on the learning curve for their defined EUDs, and how each challenge presented the EUDs with yet another demanding part of the development process. Their proposed solution is to provide the EUDs with the guidance they need to overcome these challenges--a sound, but fairly obvious proposition. On the other hand, the lack of design guidance shouldn’t be surprising, since at such an early stage of adoption, it is frequently unclear what techniques will work for users in general.