The fidelity of a prototype refers to how closely it resembles the final product in terms of appearance, functionality, and interactivity. Depending on your goals and constraints, you can choose from low-fidelity, medium-fidelity, or high-fidelity prototypes. Low-fidelity prototypes are the simplest and cheapest to make, as they use basic materials and tools, such as paper, sketches, wireframes, or mockups. They are useful for exploring and validating concepts, generating feedback, and iterating quickly. Medium-fidelity prototypes are more realistic and detailed, as they use digital tools, such as software, apps, or websites. They are useful for testing and refining features, functionality, and usability. High-fidelity prototypes are the most complex and expensive to make, as they use advanced tools, such as code, hardware, or 3D printing. They are useful for demonstrating and evaluating the final product, as they mimic its look, feel, and behavior.
The key to prototyping on a budget is to choose the right fidelity for each stage of your product development process. You don't need to start with a high-fidelity prototype if you are still exploring your ideas or testing your assumptions. You can save time and money by using low-fidelity or medium-fidelity prototypes first, and then gradually increase the fidelity as you move closer to the final product.