Android and iOS run on a variety of devices that offer different screen sizes and densities. Although these devices will automatically scale and resize images to make your web application work on different screens, this only occurs after the full-size image has been delivered. It is better to make the effort to optimize your application to receive appropriately-sized images for different screen sizes and densities rather than relying on each device simply fitting images to its screen. Doing so maximizes the user experience for all users, on any device.
That said, it can be a significant effort to maintain a set of different variants of the same image at different sizes and/or resolutions.
Using our Image Adaptation service eliminates the need to maintain multiple variant copies of images and allows you to deliver to all devices (including desktops) by maintaining a single high-resolution instance on the server, thereby saving on storage and delivery costs.
Image Adaptation allows resizing of JPG, PNG, GIF and Animated GIF images upon request to a specific pixel size or a relative percentage of the original image. Processed images are cached and re-used on subsequent requests.
You can, for example, scale down full-size desktop images by 50% for user agent headers that tell you the device is an iPhone or 75% for user agent headers that tell you the device is an iPad. You can also scale down to specific dimensions (like 800 x 600) in pixels.
Image Adaptation also provides a cropping mechanism to improve framing and accentuate subject matter. You can specify cropping dimensions and choose to crop from any of the image corners, from the center of each side, or around the center of the image.
For details please see our document What is Image Adaptation?
If you have any questions, please contact us.