Another way to reinforce an impression of sturdiness and weight is to build screens that stay put—no scrolling required. When it's possible to comfortably fit a screen's content into a single no-scroll view, you should go for it. The "out of sight, out of mind" effect is especially strong on the iPhone, where distracted mobile users speed through apps. When info isn't front and center, chances are good they won't see it at all. It's a matter of both brain and strain: scrolling requires extra thought as well as extra swipes, and one of your jobs as app designer is to reduce both.
This might seem subtle, but just asking users to figure out that they need to scroll requires them to fire up brain cells: "Wait, what's missing, and how do I get to it?" By contrast, taking in a screen's complete content at a single glance lets users focus exclusively on the content without making their gray matter do any background processing about what's offscreen. This might seem like coddling—seriously, it'll break their brains to scroll?—but the best apps bend over backward to reduce the overhead required to work the app itself. No-scroll screens require less brainwork while also reinforcing the illusion of your app as a physical, not virtual, device. A fixed screen gives a sense of solidity.
The point here is not to avoid scrolling at all costs (this section is titled "Be a Scroll Skeptic"—not a zealot, reactionary, or dogmatist). Eliminating the scroll is just one tactic for designing a display that's easy to absorb, not a goal in itself, but when it suits your app's content, it's a design tactic that encourages healthy restraint.
There's a whole category of apps devoted to the single-screen display. Apple dubs them utility apps, narrowly focused tools that provide quick summaries or perform a simple task, almost always in simple no-scroll screens. The built-in Weather app is the quintessential utility app. It provides streamlined forecasts for up to 20 cities, each tidily presented in a get-it-quick, no-scroll view—you flip through them like cards. The app's presentation lets you absorb the week's forecast for each city with just a glimpse. The carefully contained layout makes it instantly clear that there's no additional info below the fold, no "Is there more?" thinking required.
Figure 3-21. The Weather app offers a compact weather forecast, summarizing a week's weather in a single screen. The border around the info creates a solid container to signal that there's no additional scrolling content below. The page indicator dots at screen bottom indicate that more screens await (see Flat Pages: A Deck of Cards (or Just One) for more info about page indicators).
The Weather app pulls off its single-screen layout by stripping content down to the bare minimum. A few icons and high/low temperatures hardly tell the whole story of your local weather, a topic that occupies entire websites and 24-hour weather channels. Instead of indulging in complex detail, the app focuses on giving the quick gist in a simple and efficient display. This just-the-basics approach is a good strategy for utility apps, the simplest class of iPhone software. Like Weather, the best of these apps rely on graphically rich displays to telegraph simple info quickly, with big can't-miss text and images that sink in with just a quick peek. Contrary to what you might expect, the success of compact interfaces often relies on big text and chunky images cushioned with generous surrounding space. Apps pass the glance test when you can hold them at arm's length and still soak up their info effortlessly.
The glance test reinforces an essential principle of tapworthy app design: clarity trumps density. A crowded screen creates more work and confusion for your audience. This doesn't mean you're obliged to chuck your app's detailed info in order to have a beautiful and intuitive interface. It's not an either-or bargain. Complexity itself isn't bad; the trick is making complexity seem uncomplicated. Even within the iPhone's tiny screen, it's possible for apps to reveal complex information in a simple display—and yes, without scrolling.
Figure 3-22. From left, apps like Surf Report, Delivery Status Touch, and Tea Round pass the glance test with high-impact text and graphics that are easy to read even from several feet away. Surf Report shows water conditions, Delivery Status Touch shows package whereabouts, and Tea Round shows whose turn it is to brew the tea.
The AccuWeather.com app, for example, is a sophisticated alternative to the Weather app that steps beyond the utility category by providing several screens of detailed weather info. Each of these screens (see Be a Scroll Skeptic) is self-contained in a no-scroll display, providing dense information layered in multiple but uncomplicated views. Want to find out what the humidity will be in a few hours? Tap the desired hour in the app's 15-hour forecast and the details pop up immediately. The main screen shows the big-picture overview, and the app tucks additional details behind tabs or icons instead of piling it all into the same screen at once. It's at once intuitive and information-rich, no scrolling or crowded layout required.
Healthy scroll skepticism means recognizing that you don't have to reveal all your information in one shot. It's a bit like the art of conversation: don't be that guy who drones on and on without pausing to check if he's saying something that actually interests his suffering listeners. Especially when there's lots to be said or explored, the best conversations are interactive, with listeners allowed to ask questions instead of passively receiving info. In an app, a tap is effectively a question in the conversation. The best apps provide top-level, need-to-know information at a glance and, from there, let users tap something to "ask" for more information about it. Chances are, you don't need to know what the local wind speed will be at 3 p.m. every time you launch AccuWeather.com, but when you need it, the answer is just a tap away. In the meantime, the main view still gives you the basic at-a-glance info that you'd get from the built-in Weather app.
Figure 3-23. AccuWeather.com's simple tab control lets you flip between current, hourly, and daily weather forecasts. On the hourly and daily views, you can tap the day or hour to get more info—an intuitive way to make data available without crowding too much into the display at once.
Are all these extra taps really better than scrolling? Just on the basis of physical comfort, a tap is an easier gesture than the swiping scroll. A more important consideration than tap quantity is tap quality. As long as there's an appropriate reward waiting on the other side of every tap, extra taps are okay—and usually less of an imposition than a long scrolling screen. If you focus the main screen on the most important tools and info, you can safely tuck secondary content into another view. If done right, tapping through fixed screens requires you to do less visual scanning than it takes to locate content on a scrolling page. Content and controls on a fixed screen remain reliably in the same place visit after visit, so it's easy to duck in and out of an app to get the info you want without pausing to get your bearings.
Even long-form content allows creative alternatives to scrolling. Most apps for reading books, for example, use a page-turning metaphor instead of scrolling to advance the text. This lets you tap the screen just once to flip the virtual page to a fresh screen of prose, sparing you constant swiping while also reinforcing the illusion of handling a physical object—convenient and familiar. Instapaper Pro, an app for saving and reading lengthy online articles, likewise offers an option to page through screens a tap at a time. The app also offers scrolling but with a clever ergonomic gimmick to spare you swipe-swipe-swipe tedium: you can scroll just by tilting the phone back and forth to advance the text.
Figure 3-24. Stanza and Instapaper Pro offer thumb-sparing alternatives to swiping through long text. Like most ebook readers, Stanza (left) lets you tap the screen to flip to a new page of text. Instapaper (right) offers a tilt-scrolling feature to advance text by physically tipping the device.
But let's not be strident anti-scrollers. While it's good to avoid scrolling where appropriate, it's not like it's inherently evil. It's part of the fun of the iPhone's physics, and it's obviously essential to some apps. To-do lists, news feeds, articles, and emails inevitably run long, and scrolling is (usually) the best way to handle those kinds of long-form content. List-based interfaces that try to wriggle out of a scrolling screen often just feel awkward (see the interfaces the USA Today designers experimented with in All the News That Fits).
When your app does require scrolling, just be sure to keep the primary app controls anchored in one place. In early versions of the Facebook app, for example, the tab control for flipping through a friend's profile content was itself part of the content area, which meant it scrolled out of view with the rest of the page. When you finished reading through a pal's status updates, for example, you had to scroll back up to the top of the screen to switch over to your friend's photos—assuming that you could even remember where you last saw those tab controls. Facebook 3.0 remedied this where'd-it-go problem by anchoring the wayward tabs to the bottom of the screen, saving both time and head scratching. The lesson: scrolling or no, a view's primary controls should never skitter offscreen. Anchored elements create a sense of stability and consistency.
Figure 3-25. In Facebook 2.0 (left), the control for switching between wall posts, profile info, and photos was part of the scrolling content area and could disappear offscreen. In Facebook 3.0 (right), the tab control is always anchored to screen bottom.
Ergonomic and visual simplicity should be important goals for your app design. Whether or not you ultimately decide to include scrolling screens, approaching the scroll with skepticism asks you to be more discerning about what you include. Committing to the iPhone's 320 × 480 footprint puts limitations on your design as firm as if you were designing a real-world device. When there's only so much room for your tools, controls, and content, you have to ask yourself a useful question: "Do I really need all this stuff?"