It doesn't take an Einstein to realize that time is relative (file under "time flies when you're having fun.") Stuff happens faster or slower depending on the environment, distractions at hand, and the tedium of the task. As your app's interface designer, you happen to have control over all three. The choices you make and messages you convey affect the perceived time that it takes your app to complete its tasks. No matter how long something might actually take, all that really matters is how fast it feels. You've already seen how clever use of your app's launch image can make load times seem shorter (page 223). Other interface sleight-of-hand tricks enable similar illusions for bending time through good communication, misdirection, and outright distraction.
Never underestimate the power of the homely progress bar. This tried-and-true interface control displays a bar that fills from left to right as a task proceeds, providing a visual guesstimate for how much time remains. (Many apps supplement a progress bar by counting down the estimated time remaining, too.) You might think that this kind of clock-watching would just make the whole operation seem even longer by drawing undue attention to the remaining time. On the contrary, studies show that people say a process finishes faster when accompanied by a progress bar than without, even when both take exactly the same amount of time. On-hold telephone services, take-a-number deli counters, and package-tracking delivery companies all reveal the same lesson: it's powerfully calming simply to know how much longer you have to wait.
For processes that last more than a few seconds, you should offer a hint, if you can, about how soon the task will finish. Progress bars are ideal for that, and the iPhone's set of standard controls include two styles of progress bars: a skinny one that squeezes into the toolbar, and a fatter one to use elsewhere in your layout. If you're feeling more adventurous, design your own progress indicator, like the filling circle used by Shazam, the song identification app. All of these indicators provide reassurance not only that work is being done but also a visualization of honest-to-god progress being made.
Figure 10-10. Mail (left) uses a standard progress bar to show how much time remains for sending a message. Shazam (right) uses a custom progress indicator to count down the remaining time it needs to identify a song.
For a very long process, consider whether you might offer your audience something to do or read while they wait. 37signals Highrise is a companion iPhone app to a web service that manages your contacts, conversations, and meetings. Trouble is, when you launch the app for the very first time, it has to sync with your online account; if you have a lot of data to download, it takes a while, not exactly an inspiring welcome to the app. "One of the downsides to the initial download is that it can take some time depending on your connection and the number of contacts you have," admits Alex Bridges of 37signals. "Waiting for anything sucks, but what sucks more is being bored while waiting. So we decided to give you something to do while the initial download is in progress. You can play tic-tac-toe while you wait." And indeed, while a progress bar inches along the bottom of the screen, you can sling Xs and Os to pass the time.
Clever diversions don't have to be games; consider what you have in your arsenal to distract your audience during very long waits. Personal stats, relevant articles, tips for using the app—any of these things can help pass the time. As you learned back in Chapter 2, the best boredom busters give people something to explore (page 37).
Of course, the very best way to make things seem faster is to make them actually faster. Stuff takes as long as it takes, sure, but planning ahead lets you stockpile content so that you have it on hand when your audience asks for it. After loading a news-feed screen, for example, the Facebook app goes ahead and fetches the next level of content. "I wanted people to have the satisfaction of being able to act immediately on the items in the feed without having to wait for new things to stream over the network," says Facebook developer Joe Hewitt. "If you want to read the comments on a post, for example, the first few comments are all preloaded, so you can tap right through to them without having to wait at all."
Figure 10-11. 37signals Highrise distracts with a game or three of tic-tac-toe during its initial data download.
No matter what, you should give people something whenever possible—even stale info—instead of serving them a blank screen and making them wait for more. (When you're in the dentist's waiting room, it's better to have last year's Life magazine than nothing at all.) As you saw in The Illusion of Suspended Animation, saving the content or data from the last session creates an impression of fast app launching; for networked apps, it has the additional benefit of allowing you to show the last batch of downloaded content even if there's no network connection. The illusion of suspended animation isn't just about speed, it's also good manners. Emily Post would tell you that in polite company, one never lets a guest go hungry.