Smart Bikes/ Exercise Bikes comes with a smart interface that can record data, set routine, and have a live workout session on a screen attached to the stationary bike. Although they do not require any assembling, they are not portable also.
Smart trainers have become a next-level thing in Indoor cycling. It brings you all new technology and the gaming experience of virtual cycling world where you actually ride and game.
To get an ultimate comparison between the two, it is important to analyze the pros and cons of each.