Responsive (or Adaptive) design means that your design adapts to the screen it is viewed on. Simply put, smaller screens have less space. You can’t fit as much on the screen, and the layout adjusts accordingly. People expect to be able to take training wherever they are, with whatever device they happen to have in their hand.
From my research, the average person checks their smartphone nine times an hour. So, as a result, it seems that modern learners want multi-device learning. They want to learn on their own time, on the move and on their own devices. Knowing what learning content works well on mobile devices (and what doesn’t) will help you decide where to focus your time.
Consider responsive design at the beginning of your project, so you can really save time further down the line. Ask yourself if the project needs to work across all devices and view modes, or if there is a particular device that you know your learners are going to be using. You also need to think about the amount of on-screen content and complexity of interactions at an early stage in the project. This will help you avoid issues down the line.