Re5quare prepares a landscape or portrait image from your photo albums to allow uploading it to photo sharing sites that only accept square images. It does this by centering your image inside a square frame just large enough to contain the image.
You choose the fill color and whether there should be a shadow under your image. Once you are happy with your choice, simply save it. Your photo sharing app can find it later - in Camera Roll or Saved Photos - for uploading.