Microsoft has been investing heavily in Dynamics products over the past few years. Twice a year Microsoft rolls out new features and improvements to the customer experience.
In 2017, Microsoft introduced the Unified Interface which many Dynamics 365 customers have found intuitive and improved the navigational experience.
Microsoft has decided to retire the existing Web Client interface, and as of December 2020, all Dynamics 365 customers will be transitioned to the new Unified Interface. Microsoft will start transitioning customers beginning in January 2020.