Purdue's OWL website features Changes in the 7th Edition, a guide to major differences APA introduced in fall, 2019.
See also: What’s New in the Publication Manual of the American Psychological Association, Seventh Edition (APA website, 7 page PDF)
Zotero ("zoh-TAIR-oh") is a free research tool that allows you to:
Learn more at Zotero.org or visit the Smith Libraries guide to Zotero.
Offers a well-designed interface and many new features.
Visit the Citation Tools page for more information on RefWorks 3.