HoloLens, and mixed reality (MR) applications in general, offer us a glimpse into how we will soon be interacting with our computers. It will be an era where we are freed from the desk, an era where computing is brought into our world--a continuation of what the Smartphone has started. However, with this shift, we will lose some of the comforts and norms we have become accustomed to, such as using dedicated input devices that we use to interact with our computers. This loss means that we need alternative forms of input and output, either by starting from scratch or by adopting the existing forms. The latter, using an existing language, is commonly referred to as Natural User Interfaces (NUI) and is the path that HoloLens has taken by making its primary forms of input gaze, gesture, and voice; this is the primary focus of this chapter.
This chapter's examples are based on a fictional use case of having to build an application that projects...