We’ve now conducted 6 rounds of usability studies with tablet users. The good news is that tablet usability is reasonably solid and has improved substantially since the initial batch of whacky iPad apps, which often totally confused users.
We’ve tested several generations of big and small iPads, as well as many models of Android tablets (including the Kindle Fire) and some Windows tablets (including Microsoft Surface). We found that most websites are fairly usable on tablets and need only limited adjustments to suit this environment. (In contrast, using websites on mobile phones requires many more design changes to accommodate the smaller screens.)
Not surprisingly, when we asked people how they use their tablets, web browsing was universally mentioned as a top activity.
Although tablet-specific applications have plenty of usability flaws, the problems are mainly the same as those that plague traditional application design: difficult features, a mismatch with user workflow, and poor instructions that people don’t read.
Designing and building any high-usability application involves substantial work, and tablet apps entail a few additional issues, including the need to modify the user interface for different tablet models. This, combined with the popularity and ease of using websites on tablets, begs the question of why companies would have a tablet app in the first place. In fact, we advise most companies to stick to their website and invest the resources in improving web usability, which still suffers badly in most companies.
Build a tablet app only if you can offer value-added functionality over a website, such as creating an app that is focused on supporting a single main task.
In any case, don’t make your tablet app a scaled-up phone app. We’ve seen hundreds of apps (mainly on Android) that misuse screen space by offering tablet users the same basic design as phone users.
Revenge of the Frames
In 1996, I condemned the use of frames in web page design. Sure enough, those original terrible frames are rarely seen today; improved design techniques — such as inline frames and parallax scrolling — meet similar goals with better usability.
But, like zombies, certain bad designs come back from the dead to haunt users, and frames-like concepts cause usability problems in many modern tablet designs. Two common problems are split-screen designs and temporary frames for search results and the like.
Although a tablet seems big compared to a phone, it’s still a small screen and typically shouldn’t be subdivided into smaller frames or split views, except when users really need to access two types of information simultaneously. Every time you split off part of the screen, less remains to show content.
Web UX Bleedthrough
Given the web’s dominance in computer use these days, it’s not surprising that we found concepts from the web user experience bleeding through the platform divide and influencing people’s use of tablet apps. Key examples here include search dominance and heavy reliance on the Back button.
Users frequently want to search on tablets; they also want to return to their search results. Unfortunately, many apps don’t provide a proper SERP (search engine results page) as a primary navigation object that users can easily return to. Instead, search results are shown in one of those zombie-attack frames with a fleeting screen presence.
The Back button has long been the user’s lifeline on the web; if anything, it’s even more important on tablets, where accidental activation is a common consequence of the touchscreen interface. Unfortunately, even with apps that did offer Back, our testing revealed periodic usability problems: sometimes the feature was hard to find, while other times it didn’t undo the user’s last action as expected.
Gestural user interfaces have several inherent problems that tablet apps need to minimize:
Accidental activation: users often touch things by mistake and need a way to undo the result.
Swipe ambiguity: when the screen is divided into subregions (such as the frames we caution against), the same gesture can have different effects, depending on where it’s activated. This problem is exacerbated by the trend toward flat design, which doesn’t clearly demarcate the regions.
Invisibility: users can’t see the gesture they just made, and they sometimes can’t even see what they’re supposed to touch. Again, flat design makes this worse.
Low learnability: all of the previous problems combine to make gestures hard to learn. Advanced gestures might as well not exist, as very few users employ anything beyond the basic tap, press, swipe, drag, and pinch gestures.
Despite these inherent problems, most of the tablet apps we tested employed gestures reasonably well. The exaggerated skeuomorphism of the early days has also subsided.
The two main threats to tablet usability are:
Flat design. Why not allow users to easily see what they can do? We need a golden middle ground between skeuomorphism and a dearth of distinguishing signifiers for UI elements.
Rescaled design. Whether shoehorned down from a bigger screen or grotesquely exploded from a phone screen, too many Android designs simply don’t fit the tablet’s actual screen size. (Poorly rescaled designs are less common on iPad and Windows tablets, probably because of smaller device diversity.)
The flat design threat is a fashionable trend that will hopefully subside before it hurts users (and companies) too much. The second threat will be with us longer, because it’s caused by resource constraints and the naïve idea that a single design is good enough as long as it adapts to the available screen space.
Full Research Report
The full research report with 126 usability guidelines for tablet user experience is available for download.