Prototyping with Principle: A Quick Review

I’ve partnered with my client, Texture, for more than two years, and I am still continually learning in all aspects of design. I’ve been lucky enough to pick up two software programs in the last year; Sketch and Principle. I’d like to give a quick review of Principle and share my pros and cons as a new user

Why Principle

The design team at Texture recently introduced Principle into their workflow as a tool to create interactive prototypes that will assist in delivering design specifications to developers, project managers, and other stakeholders involved. The intention is to hand over an interactive, realistic visual of what us, the designers, are trying to achieve, which will complement the static mockups and wireframes. The prototypes will serve as a communication tool, as well as a way for us, designers, to flesh out ideas and make decisions.

There are a lot of prototyping tools out on the market right now, but Principle software is very robust and at an affordable price of $129, it allows designers to jump right into creating elegant prototypes that translate their ideas.

The design team at Texture mainly utilizes Sketch for mockups and to illustrate user flows. The fact that Principle integrates with Sketch and allows complete import of Sketch files (which includes all layers and some properties) means a more efficient workflow. No one wants to spend tons of time or money on the prototyping phase, so anything that can assist in trimming that cost will help, especially when you’ve done a lot of the work already; it’s just a matter of stringing the designs together and adding the layer of interaction and animation.

Pros and Cons

Pros

• Easy to pick up after taking a simple online course. It has similarity to familiar design tools like Sketch.
• Is a robust application that can create very elegant animations, transitions, and interactions for anything from a multi-screen app prototype to an animated GIF.
• You don’t need to know how to code.
• Real-time preview panel allows you to test and edit your project quickly and efficiently.
• You can import full Sketch files into Principle and retain layers and properties; however, there are limitations to the features that Principle recognizes in Sketch layers (more about that below in “Cons”).
• You can export in different formats: video of your design and interactions; animated GIF of your design and interactions; a standalone Mac app that anyone with a Mac can open; Principle Mirror app for iOS can display Principle documents.
• Principle’s “repo” is a great resource where you can find inspiration and download source files that show you how to achieve the sleek animations that inspire you.
• Principle’s Resources section of their website is a nice aggregate of resources that will help you as a Principle user. Included in that list is the Principle Community on Facebook which has almost 11,000 members.

Cons

• Principle is a Mac only software. It runs on Mac OS X 10.10 or newer (Principle Mirror, their iOS reflecting app, runs on iOS 8 or newer).
• Prototypes, while possible to design around iOS, Android, and web, can only be previewed on a Mac or on an iPhone.
• Principle doesn’t export to CSS, Framer, Xcode, Android Studio, or React Native.
• Principle doesn’t export animation values, but engineers can see them in Principle. These values are platform agnostic.
• When importing Sketch artboards, some properties will not be recognized by Principle which will result in the layer being imported as a flattened image. The properties that will be affected are: Paths, Fills, Borders, Blur and other effects, Masks, and Text layers.
• No ability to create assets inside Principle. Editing capabilities are limited to the basics (like scale, rotate, etc.).
• Preparing and using retina image assets for a mobile project is confusing for me; but I imagine this is just due to the fact that I haven’t done it enough.

Conclusion

Principle is a great prototyping tool that will assist you in fleshing out your ideas and communicating them to your team. While there are limitations, Principle was only launched in 2015 and is continually being improved. There is a large community that serves as a great resource and individuals are creating beautiful projects with the software. I encourage you to try out the 30-day free trial to get your feet wet, and after doing so, go ahead and dive into creating your own awesome prototypes!