Proto.io

Design and customize realistic web and mobile app prototypes with interactive elements, audio/video, and easy sharing.

What is Proto.io?

Proto.io is a browser-based prototyping tool that lets you design interactive prototypes for web and mobile apps without writing code. You build prototypes by arranging UI elements, adding interactions, and including media like audio and video. The tool focuses on making prototypes look and behave like real applications, so you can test user flows and get feedback before development begins. It's aimed at designers, product managers, and UX researchers who need to communicate ideas quickly to stakeholders or validate design decisions with users.

Key Features

Interactive prototyping

add clicks, swipes, gestures, and transitions to create working prototypes

Asset library

pre-built components and UI kits to speed up design work

Media support

embed videos, audio, and animations directly into prototypes

Sharing and collaboration

generate shareable links for feedback and testing without requiring recipients to have an account

Mobile and web templates

start with pre-sized frames for common devices and screen sizes

Animation and micro-interactions

add timing, easing, and layered animations to enhance realism

Pros & Cons

Advantages

No coding required; anyone can build functional prototypes
Browser-based, so no software installation or OS restrictions
Easy sharing via links makes gathering feedback straightforward
Responsive design tools let you design for multiple screen sizes in one project

Limitations

Limited to prototyping and interaction design; not suitable for final production code
Performance may lag with very complex prototypes or large asset files

Use Cases

Testing app flows with real users before building the actual product

Presenting design ideas to clients and stakeholders with working demonstrations

Designing and testing responsive web layouts across devices

Creating interactive portfolios or case studies for design work

Validating user journeys and identifying usability issues early