Many people rely on what I will call linear presentation tools when they lecture. This includes software such as LibreOffice Impress, Google Presentation, MS PowerPoint, or Keynote. These tools are great for smooth, timed, linear lectures. I also use them from time to time, but mainly if I know exactly what to say. They are also good when I lecture with others, and we need to develop a presentation together. However, linear presentation tools do not work equally well for general teaching, where spontaneity is required.

Apple’s Keynote has been my preferred presentation tool for about a decade. For a long time it felt like the ideal tool, easy to use, powerful and flexible. But at some point, probably around the time when the iOS version of Keynote came along, the Mac version of Keynote started loosing features and became more limited than it had used to be. Since then, I have experienced all sorts of problems, including non-compatibility of new and old presentation file versions, problems with linked video files, crashes, etc.