Systems and processes for prototyping and designing natively rendered multi-channel applications across diverse platforms are disclosed. The method of prototyping an application with a computing device includes providing a library of native design elements which are reproducible in different design layouts on an interface associated with different, predefined platforms. The method further includes converting a first design layout comprising one or more native design elements which fits within an interface associated with a first platform of the different, predefined platforms to a second design layout comprising the one or more native design elements which fits within an interface associated with a second platform of the different, predefined platforms, and which is in proportion to the first design layout.