You see an amazing moment caught on iPhone video... in portrait instead of landscape. Sigh. You watch an unforgettable scene unfold before your eyes... sideways. Ugh. You see the most beautiful memory imaginable... that's so crooked it looks like it's sliding off the edge of the world. Rage. If you know someone who absolutely, positively just can't get their videos right, grab their phones, punch Horizon into the App Store, and have them buy it and use it. Yes, the greater the angle of rotation it has to fix, the lower the resolution of the video will turn out, but that's the price that has to be paid to straighten it out.
Because friends don't let friends screw up their movies.