The National Library of Medicine has announced that the new version of PubMed will become the default search platform on May 18, 2020. The "legacy" platform will remain available and continue to receive citation updates until September 30, 2020.
The new version has been available for approximately a year, with adjustments and improvements being made in response to user feedback. One of the most visible improvements is the responsive design of the new site. Responsive design means that the site can be used on any device - mobile, desktop, or tablet - with the same features and functionality. Previously, only a very basic version of PubMed was available on mobile.
See New Pubmed for more information about the updated searching platform.