(http://readwrite.com/files/fields/instagramstraighten.png)
Instagram added a "straighten" function to its app (http://instagram-engineering.tumblr.com/post/59423716308/making-it-simpler-to-take-more-beautiful-photos), one that auto-corrects photos to the straight and narrow just as you'd expect. The same function also lets users manually rotate and adjust an image as they see fit.
To read more about how to use this new feature and how Instagram designed it specifically with an eye toward simplicity, read its blog post here (http://instagram-engineering.tumblr.com/post/59423716308/making-it-simpler-to-take-more-beautiful-photos).
Image courtesy of Instagram
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