You can download the update directly through the Windows Store or by using the following link:
Additionally Amazon’s Whispersync technology automatically syncs your furthest page read, bookmarks, notes, and highlights across all your devices that have the Kindle app installed and across any Kindle device. That means you can start reading on one device and pick up where you left off on another.
The Kindle for Windows update has the following new features and improvements:
- New! Search inside the book
- New! Redesigned home screen
- New! Sample recommended books
- New! Redesigned in-book navigation
- New! Easier bookmarking
- New! Redesigned Notes and Bookmarks with filtering
- New! Live Tile displays the book you’re reading
- Updated! View options menu
- Updated! Library and search views
source: Microsoft-News