The zentools framework is based on a mobile ready css and javascript framework. This means that regardless of the device your user is viewing your site on, the module content is optimised for the dimensions of that screen dimensions.
Simply grab a tag for the title, text, image, category (and more) into the layout box and your custom module layout is created. Simple.
Take the pain out of resizing your images. The Zentools built in image resizer can easily scale, crop and resize your content images. In addition to this you can target different images for different screen sizes giving you full control over how your images display across multiple devices.