A prototype is a quick, rough implementation of a future application.
A prototype is a medium to high-detailed representation of the final product that mimics the user's interaction with the interface.
The goal of prototyping is to understand how an app will look and operate in the shortest time possible to avoid design errors in later stages.
Prototyping not only provides a clear visualization of the design to understand the look and feel of the final product, but it also helps the developer understand what they are designing, for whom, and why.
Learn more about mobile app wireframing.