Affordances and Constraints of Apps

Apps present an interesting design construct when it comes to affordances. As the gateway to almost all of the digital content we consume, the app is a crucial piece of the digital world. We use them every day, for a myriad of purposes.


The first design element I notice about the app is its shape on the screen. Designing the app as a button icon affords a “pushing” (or tapping) action. We are familiar with buttons, and already know what to do with them when encountering one. The icon will usually consist of an app-relevant picture with the title of the app underneath, similar to a book or album cover. The app is positioned in a grid next to other apps. We are familiar with this concept of a row/grid of various titles from the other marketplaces of audio/visual content, like movie stores, book stores, or music stores. One constraint of this process is 2D substrate of the device. Unlike books or records or DVDs/VHS tapes, you cannot pick up the app and manipulate it in 3D. There is no back cover of the app, which is where a lot of information was stored in those older forms of media. This constraint can often be played with, or overcome, through the design choices of the particular app. There is a relatively infinite amount of information that can be stored on digital apps, and can be accessed through scrolling, which is a digital affordance we now have.

Opening the app

Once clicked, the app springs to life by covering the entire screen of the device. The phone/tablet turns from a marketplace of potential uses into a tool for one. The software takes over the entire screen of the device, allowing for not only a much larger range of visual features, but also the multi-touch features of the touchscreen. The full screen also affords a larger share of attention to the particular app. One constraint of this app interface is, again, the 2-Dimensional substrate. You cannot open an app the same way you open a book or album. The entire process takes place on a flat grid.

Design Principles

The designer of the app has to contend with the unique constraints of digital devices while pulling from the affordances we expect from traditional media and devices. The Murray reading did a good job of explaining how the introduction of digital media meant a new school of design was needed to explore this “problem”. Nowadays, we are building on this already established school of digital design affordances, but there is always more to add and refine. One of the central lessons I have gleaned from this course, so far, is that design is an exercise of choice. The individuals and institutions that have guided our design processes so far have made conscious and distinct choices to follow certain affordance paths and move away from certain constraint paths.


1. Murray, Janet. Inventing the Medium: Principles of Interaction Design as a Cultural Practice. Cambridge, MA: MIT Press, 2012.

2. Kaptelinin, Victor. “Affordances.” The Encyclopedia of Human-Computer Interaction, 2nd Ed., 2013.

3. Norman, Donald. “Affordance, Conventions, and Design.” Interactions 6, no. 3 (May 1999): 38-43.