Well essentially the platform simply looks at the difference between the width and height, and rotates to fit a 4x6 aspect ratio, gravitated towards the center

Well essentially the platform simply looks at the difference between the width and height, and rotates to fit a 4x6 aspect ratio, gravitated towards the center of the photo. It works best with photos taken directly from a smart phone, uncropped. It also scales the resolution if its not high enough, but this typically isn't an issue if the photo was taken with a modern smartphone today. You can read a bit about this in FAQ https://postcardbot.co/faq https://postcardbot.co/faq