Category: User Interface

Putting the Best Face on an App, Apple Style

Every application developer goes through a series of development steps:

  • Speak to potential users
  • Get a feature list
  • Collect functional requirements
  • Prioritize functional requirements
  • Set non-functional requirements

Typically, after the main functional and non-functional requirements are set, only then does the user interface and user experience get much attention. No doubt, this is what contributes to the problem of poor usability in clinical software. Ratwani (1) and colleagues have demonstrated that EHR vendors tend to be all over the map when it comes to user-centered design.

To some degree, the variation (or even absence) of sound UCD methods among clinical software vendors is understandable—there are no standard user experience (UX) or UI guidelines for clinical software.   I am not excusing them, only saying that the problem of UX/UI for clinical software requires investigation beyond the resources of most vendors. There is also the problem of knowing how to get started. Assuming money is available for UCD R&D, the question still remains of how to get started. What skill sets are required? Who should lead the effort? What is the best way to recruit users? What data should be collected, and what processes and interactions studied?   While user involvement is standard for any software project, UCD usually is not – thus the situation reported by Ratwani and colleagues.

In the last post, I spoke about my UI and UX concerns. I want an app that connects with the user and makes the experience of using the app functionally and aesthetically-pleasant. One unexpected, but very much welcome, source of assistance has come from Apple.   Apple has put together a guide that details the proper ways to design iOS applications (iOS Human Interface Guidelines) (2).   The guidelines address the complete range of UI issues. Apple also provides guidance for structuring apps – such as when to use a show-detail view as opposed to an add-item view when using table views to present information. Taken together, the hints and guidelines offered are a practical, accessible course on usability.   What I had thought would be a constraint on creativity has proven to be a source of enlightenment!   From the perspective of prn: OnCall, the challenge is how to package the required functionality into a pleasing app using Apple’s guidance.

A Quick look at iOS HIG
The guide is extensive (over 150 pages in printed version) and begins with a set of core design principles, then delves into the specifics of how to use iOS features to conform to those principles.   They are presented below.

Aesthetic Integrity
Aesthetic integrity represents how well an app’s appearance and behavior integrate with its function. For example, an app that helps people perform a serious task can keep them focused by using subtle, unobtrusive graphics, standard controls, and predictable behaviors. On the other hand, an immersive app, such as a game, can deliver a captivating appearance that promises fun and excitement, while encouraging discovery.

A consistent app implements familiar standards and paradigms by using system-provided interface elements, well-known icons, standard text styles, and uniform terminology. The app incorporates features and behaviors in ways people expect.

Direct Manipulation
The direct manipulation of onscreen content engages people and facilitates understanding. Users experience direct manipulation when they rotate the device or use gestures to affect onscreen content. Through direct manipulation, they can see the immediate, visible results of their actions.

Feedback acknowledges actions and shows results to keep people informed. The built-in iOS apps provide perceptible feedback in response to every user action. Interactive elements are highlighted briefly when tapped, progress indicators communicate the status of long-running operations, and animation and sound help clarify the results of actions.

People learn more quickly when an app’s virtual objects and actions are metaphors for familiar experiences—whether rooted in the real or digital world. Metaphors work well in iOS because people physically interact with the screen. They move views out of the way to expose content beneath. They drag and swipe content. They toggle switches, move sliders, and scroll through picker values. They even flick through pages of books and magazines.

User Control
Throughout iOS, people—not apps—are in control. An app can suggest a course of action or warn about dangerous consequences, but it’s usually a mistake for the app to take over the decision-making. The best apps find the correct balance between enabling users and avoiding unwanted outcomes. An app can make people feel like they’re in control by keeping interactive elements familiar and predictable, confirming destructive actions, and making it easy to cancel operations, even when they’re already underway.

Branching out from these principles, the guide addresses the use of specific interface elements. Having used plenty of iOS apps, I still found the advice on various navigation methods: navigation bars, toolbars, tab bars, etc. to be informative and useful.

On reading the guide, I realized that I was very much stuck in the desktop view of how an application is organized and accessed by the user.   For example, early on, I spent a while searching for the iOS equivalent of a drop-down list.   Then, after finding that table views were the iOS way, I rebelled and complained thinking table views were too complicated for such a simple task. Of course, once I understood segues, how to populate table views with data, and how to build custom cells, table views seemed far more useful than drop-down lists. Lesson learned…

Although I had heard about Apple’s focus on design and knew the guidelines existed, I held negative, pre-conceived notions of the guidelines. Sort of, “why are these guys telling me how to design an app?” Well…they DO know what they are talking about. I suppose, part of my reaction was due to having read Microsoft’s comparable guide for Windows desktop development.   Microsoft’s materials were also quite helpful; but, in retrospect, seemed to focus more on the technical aspect of usability (no complaints). Apple’s focus, on the other hand, adds more in terms of aesthetic hints and suggestions. There is more of an emphasis on the “beauty” of an app and the pleasantness of the user experience in addition to usability.

The most recent guidelines are web-based. However, I have a printed version from a few years ago that I think is a superior reference (especially new developers) because it contains information about the fundamentals of developing an app from engaging users to prototyping and iterating until reaching a final product. That information is presented clearly and succinctly. Along with the actual interface design information, it presents a great intro to the world of professional software design.   Comparing the online version to the older printed one, I really wish they continued offering the printed version.

For quite some time, I had dreaded downloading the iOS Human Interface Guidelines. Expecting a dry bureaucratic document, I was more than pleasantly surprised to find an excellent reference and friendly tutorial. Just goes to show that, as Fats Waller would say, “One never knows, do one?”

  1. Ratwani RM, Hettinger AZ, Fairbanks RJ. Barriers to comparing the usability of electronic health records. J Am Med Inform Assoc. 2016 Aug 29. [E]
  2. iOS Human User Interface Guidelines. Apple, Inc.