A new version of WinSnap has been released today. It adds the Highlight tool and contains several other minor tweaks, enhancements and performance optimizations.
Now you can easily highlight text and rectangular areas on your screenshots:
Small enhancements to Arrow and Pen tools:
For Pen, hold down CTRL or SHIFT:
Changelog for WinSnap v4.5.2 (April 1, 2014):
New Highlight tool to highlight text and rectangular areas on screenshots
Hold down CTRL key to draw arrows perfectly at 0, 45 and 90 degrees
Adjusted minimum height and width of the main window
Fixed SHIFT + Number to select drawing tools
Main window restores default size on DPI change
Several performance optimizations for Colorize effects