Proto.io

Proto.io is a web-based, no-code tool for building interactive prototypes for iOS, Android, and web. It includes native iOS and Android apps, more than 250 UI components designed to mimic native behavior, and over 1,000 customizable web and mobile templates. Its library lists more than 6,000 static and animated icons, stock images, and sound effects. Prototype interactions can use over 80 events and over 40 actions, with nested and multidirectional scrolling; screens can be linked using 18 built-in transitions. Users can share links and snapshots or export to PDF, PNG, or HTML. User testing with popular testing platforms is supported. The free plan allows one user, one active project, five prototype screens, and 10 MB storage. It includes single-click sharing and exports, but no additional reviewers. A 15-day trial is listed. Freelancer is $29.00 per month; higher monthly plans are listed at $49.00, $99.00, and $199.00. Paid plans include 256-bit SSL encryption.

Proto.io combines visual components, interactions, sharing, and export options for interactive prototyping. The free plan is tightly limited in users, projects, screens, and storage; paid monthly plans start at $29.00.

Proto.io suits designers and teams who want to create and share interactive prototypes without coding. Its free plan can accommodate a small project, while paid plans offer more users and active projects.

Proto.io is a web-based, no-code tool for building interactive prototypes for iOS, Android, and the web. It suits designers who need detailed interactions and shareable prototypes; its free tier is useful for a small trial, but tight project and screen caps make paid plans the practical choice for ongoing work.

Overview

Proto.io combines a visual component library with interactions, transitions, sharing, and export options. Prototypes can target mobile and web, and native iOS and Android apps are supported. The product also supports design systems, variables and tokens, and team collaboration, without requiring a desktop app.

Key features

More than 250 UI components mimic native behavior, while over 1,000 customizable templates and a library of more than 6,000 icons, images, and sound effects give designers substantial starting material. The breadth is useful when building varied screens without assembling every visual element from scratch.

Interaction controls include over 80 events and 40 actions, nested and multidirectional scrolling, and 18 built-in screen transitions. That range supports prototypes with more than simple click-through navigation. Sharing links and snapshots at specific points in time help teams review versions; PDF, PNG, and HTML exports provide offline or portable outputs. User testing with popular testing platforms is also supported.

Granular security supports solo work or teams of any size. Paid plans include 256-bit SSL encryption, alongside industry-standard SSL security. Documentation, sample projects, tutorials, guides, webinars, and case-by-case support round out the product.

Pricing

The free plan is capped at 1 user, 1 active project, 5 prototype screens, and 10 MB of storage. It allows single-click sharing but no additional reviewers. HTML, PNG, and PDF export, design-tool import, and branding are included, making it a constrained way to explore the workflow rather than a workable team plan. A 15-day trial is also available; a limited-feature Free Account remains available after it expires.

Paid plans are billed monthly at the following prices:

Freelancer is the entry paid tier for one-person work that needs more projects or reviewers than the free plan allows. Startup, Agency, and Corporate add seats and project capacity for progressively larger teams. Annual billing shows rates of $24, $40, $80, and $160 per month for Freelancer, Startup, Agency, and Corporate, respectively. Enterprise adds SSO and enterprise-grade security with a tailored plan, making it the relevant tier for organizations that need those provisions.

Platforms

Proto.io is web based and supports prototypes for iOS, Android, and the web, with native apps for iOS and Android. Its lack of a desktop app means the workflow is web-based rather than a separate desktop application.

Who it's for

Proto.io is best suited to designers and teams that need richly interactive prototypes, broad visual assets, and reviewer sharing across mobile and web projects. Solo designers can start with Freelancer; teams should weigh the seat and project quotas against the cost of moving up. The free plan is a poor fit for work that quickly exceeds five screens or needs multiple users or reviewers.

Pros and cons

• Pros: A large component, template, and asset library provides breadth for building varied prototypes.
• Pros: Extensive events, actions, scrolling options, and transitions support more involved interactions.
• Pros: Unlimited reviewers on paid plans and multiple export formats make it easier to circulate prototypes and snapshots.
• Cons: The free plan's 5-screen, 1-project, 1-user, and 10 MB limits constrain sustained or collaborative work.
• Cons: Paid monthly plans start at $29 a month for one user, so teams must pay more to gain seats and project capacity.

Alternatives

Consider prototyping software or UI design tools if you want to compare options across those categories. For a broader design focus, see web design software or game UI design software.

• Justinmind may suit readers who prioritize a free plan with unlimited screens and viewers for one project.
• Marvel is another freemium option, with a free plan for one user and one project.
• ProtoPie offers a free plan with two saved cloud prototypes, eight scenes per prototype, and 50 MB of cloud storage.
• UXPin has a limited free plan after its 14-day trial, with two prototypes and 50 AI credits.
• Figma Slides is a freemium option with a Starter plan offering limited access to Figma products.
• HTMLhouse is a free option whose repository identifies an MIT license.
• Sketch is a paid alternative with a $12 a month Standard plan billed yearly per editor, including real-time collaboration and unlimited documents.
• Principle is a paid alternative with a license that can continue to be used after one year, though new features require renewal.

Verdict

Choose Proto.io if you need a web-based prototyping tool with a deep interaction toolkit, extensive visual assets, and flexible sharing and export. Its free plan is too small for ongoing work, and seat-based monthly pricing makes it less compelling for teams with modest needs; those users should compare alternatives with larger free quotas before committing.