Principle for Mac review: animated UI prototyping tool. See its $129 one-time pricing, features, pros, cons, and alternatives like Figma and ProtoPie.
Principle is a macOS design application focused entirely on interaction and animation: rather than being a general-purpose design tool, it takes static artboards and turns them into believable, interactive prototypes with realistic motion. It was created in 2015 by Daniel Hooper, a former Apple engineer, who built the app independently from Atlanta, Georgia before growing a small team around it.
The app has become a go-to tool for designers who need to demonstrate exactly how a screen transition, gesture, or micro-interaction should feel, something static mockup tools and even many prototyping tools struggle to convey. Its Mac-only, timeline-based approach has earned it a loyal following among UI and UX designers at companies ranging from startups to Apple, Google, and Netflix.
Principle's core is a visual timeline that gives frame-by-frame control over easing, timing, and sequencing, letting designers fine-tune bounces, transitions, and gestures without writing animation code. Designs can be imported directly from Figma or Sketch, and re-importing after edits intelligently merges changes rather than forcing a rebuild from scratch, which keeps the design and prototyping workflow tightly connected.
Beyond animation, Principle supports multi-screen flows viewed from a bird's-eye perspective, device presets for mobile, web, and desktop artboards, and live preview on a connected iOS device for testing gestures on real hardware. Finished prototypes can be shared to the web with a single click, viewable by anyone in a browser regardless of their operating system, or exported as a video or animated GIF for decks and portfolios.
Unlike most modern design tools, Principle is not a subscription product. It is sold as a one-time perpetual license for 129 dollars, which includes one year of free updates from the date of purchase, and the developer offers a 14-day free trial so designers can evaluate the full app before buying.
There is no separate free tier and no lower-priced starter plan; the single license unlocks the entire feature set. Team usage is supported through the purchase of additional seats rather than a dedicated team-pricing plan, keeping Principle's pricing structure notably simpler than most competing prototyping tools.
No, it offers a 14-day free trial and then requires a one-time purchase of 129 dollars.
No, Principle is Mac-only, though shared prototypes can be viewed and interacted with in a browser on any operating system.
Yes, designs can be imported from Figma, and re-importing after edits intelligently merges changes.
Yes, finished animations can be exported as video files or animated GIFs.
Principle was created by Daniel Hooper, a former Apple engineer, and launched in 2015.
Yes, it runs natively on both Intel and Apple Silicon Macs.
No, Principle is sold only as a one-time perpetual license that includes one year of free updates.
Principle offers deeper, frame-by-frame timeline control over animation compared to Figma's built-in Smart Animate.