The most popular API, in terms of mashup count, is far and away the Google Maps API, which accounts for 41% of all mashups. But when it comes to the most popular pair of APIs, Flickr and YouTube mashups are the most common. Not to be outdone, Google Maps joins Flickr in a near second place.
Even the most modern responsive websites often struggle with selecting image resolutions that best match the various user devices. They typically have to compromise on either the image dimensions, number of images created, or even worse, just simply use a single image with the largest resolution.