Learning happens in small increments - bits of knowledge that collectively stitch together to form mental models of understanding. So it’s only natural that online learning services minify and break up content into consumable chunks. Mobile amplifies this - shorter attention spans come with being able to consume any content on the go - we fit those moments into the day.
This concept can be extended pretty far - potentially doing away with the concept of fixed courses altogether to a more fluid learning structure. Using Microlearning structures we can eventually unbundle a college degree - although more likely is that it will helps for the construction of more specialized degrees.
Software for learning will continue to become more adaptive to how humans learn - and microlearning is a big part of that trend for educationalists tech.