Forget Skitch: My favorite screenshot annotation app is Aged and Distilled's Napkin.
Not only does [URL="https://itunes.apple.com/us/app/napkin-image-annotation-markup/id581789185?mt=12&at=10l3Vy]Napkin[/URL] let you annotate single screenshots, but you can also arrange multiple Retina-quality screenshots on a single canvas and export them accordingly. That might sound like niche software, but it's essential for those of us who need to annotate screenshots for articles, books, interface review, and other jobs involving design or production. Its latest updated, version 1.5, adds a bunch of must-have annotation features including redacting images, cropping them, and new arrow and fill shape styles.
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