"Froont is the fastest solution for designers who want to prototype responsive websites with their true content."
>at the bottom. It's for "prototypes."
During the process of developing the tool, it has evolved from a prototyping tool into a design tool. Unfortunate delay in updating the definition on CrunchBase.
Design is iterative by its nature – therefore FROONT can be used for prototypes and for designs, that depends of the stage and complexity of design. IT can be wireframing, designing responsive patterns or design with real content.