Principle is a native macOS application for designing animated and interactive user interface prototypes. It enables designers to create screen transitions, animations, and multi-screen application flows within a visual workspace. The software provides a timeline-based animation system and artboard-driven layout model. Designers can build complex interactions, define transitions between screens, and simulate application behavior without writing code. Principle supports importing static designs from tools such as Sketch and Figma, allowing users to extend existing interface layouts with motion and interaction logic. It also includes preview capabilities to test prototypes interactively during the design process. Prototypes can be shared through web export, standalone Mac applications, or via the companion iOS application, Principle Mirror. The software is distributed as a per-device license and runs natively on macOS systems. This description is based on official product pages, documentation, pricing information, and update notes.

Key Features

Timeline-Based Animation Create detailed motion sequences using a visual timeline.

• Define easing, bounce, and timing behavior
• Manage keyframes visually
• Zoom and organize animation tracks
• Stack closely placed keyframes for clarity

Artboards and Multi-Screen Flows Design complete application flows across multiple screens.

• Automatic left-to-right artboard arrangement
• Reorder artboards via layer list
• Bird’s-eye overview of all screens
• Visual transitions between artboards

Interactive Prototyping Define interactive behaviors directly within the design.

• Built-in dragging, scrolling, and paging interactions
• Hover events for web and desktop prototypes
• Live preview window for real-time testing
• Continuous interaction configuration per axis

Components System Create reusable and stateful design elements.

• Components with internal artboards and animations
• Reusable UI elements such as buttons and toggles
• Ability to freeze component state between transitions
• Reduced complexity in large projects

Import from Design Tools Extend static designs with motion and interaction.

• Import Sketch artboards and Figma frames
• Intelligent merge when re-importing
• Automatic layer flattening for unsupported features
• Order preserved from source design files

Preview and Sharing Options Distribute and test prototypes across devices.

• Detachable interactive preview window
• Share to web with one click
• Export video or animated GIF recordings
• Export standalone Mac applications

Principle Mirror (iOS Companion App) View and interact with prototypes on mobile devices.

• Open Principle files from other apps
• Mirror designs directly from Mac
• Available for iPhone and iPad
• Free companion application

Native macOS Application Built specifically for macOS systems.

• Supports full-screen mode
• Retina interface
• Auto Save
• Runs on modern Mac hardware

Benefits

Code-Free Interaction Design Design interactive behavior without programming.

• Visual configuration of transitions
• Rapid experimentation
• Immediate feedback through preview

Structured Management of Complex Prototypes Organize large design systems efficiently.

• Component reuse
• Artboard-based structure
• Improved performance in complex files

Cross-Platform Prototype Viewing Share prototypes across operating systems.

• Browser-based viewing
• iOS device preview via Mirror
• Standalone Mac exports

Integration with Existing Design Workflows Extend established design files instead of recreating them.

• Sketch and Figma import
• Re-import with intelligent merging
• Preservation of artboard order

Predictable Licensing Model Per-device licensing with defined update period.

• License per computer
• Includes new features released within one year
• Renewal required for additional feature updates