Check out the cool demos on my webinar on SharePoint Online Changes
This is an announcement of new feature in Office 365 - SharePoint Online Site Collection App Catalog and explains about that feature.
You'll learn updated features to the SharePoint Modern admin center in office 365 and how we can navigate from old admin center. Here I'll also given my comments need to improve in admin center.
This post contains the common URL locations to the modern UI pages in SharePoint.
New available properties in _SPPageContextInfo variable for SharePoint Online