Thumbr.io serves the user's images at the right size and resolution for whatever devices they appear on and can add Instragram-like filters without affecting the original file. Users only need to upload one hi-res image, and Thumbr.io makes the adjustments automatically. Thumbr.io also provides smart cropping and thumbnail generation services. Thumbnail previews of websites or documents can be generated at any size or resolution. All of these features are available programmatically via the Thumbr.io API.