Developer Curtis Herbert worries that a winter's worth of work on an Apple Watch app will come to nothing.
Herbert and other independent developers haven't gotten nearly as much guidance from the tech giant as they'd like. They've had no access to the watch to test their work, and little direction on how to land a coveted spot in the virtual Apple App Store.
Apple "might rip my app to shreds," said Herbert, whose Slopes app would serve skiers and snowboarders.
The success of the Apple Watch - set to go on sale April 24 - will depend largely on the quality of apps built for its tiny screen. But critics have questioned whether a "killer app" will emerge, one that can transform the Watch from a novelty or fashion item into a breakout hit, like the iPhone or iPad.
Such an app or apps would arise from the thousands of developers' submissions that the company plans to stock in the Apple App Store. But except for a software developer kit Apple handed out months ago, most app developers have been left in the dark.
The stakes are high for developers. It's not expensive to develop most apps, but the rewards of being among the first to offer apps could be great. It's hard for new apps to get noticed amid the million-plus apps available for iPhones and iPads. But the limited number of Watch apps now offers better odds of them going viral, said Aaron Wadler, chief executive of ShopPad.
These are the "Golden Days" for the Apple Watch platform, said Wadler, whose company is developing a Watch companion to its iPhone app, Chameleon, which notifies wearers of special deals when they walk into a store.
The potential upside, combined with the uncertainty of the selection process, makes him nervous. He has little idea what app advertising or in-app purchase design should look like.
"We're having to imagine and extrapolate and read the tea leaves of Apple," he said.
Herbert, an independent developer, is eager to see how Slopes looks on an actual watch. His iPhone version of Slopes is used by skiers and boarders to track their routes on the mountain with lively animations that show speed and altitude change. The app makes more sense on a wrist device for snow sports enthusiasts wearing gloves and heavy clothes.
Dealing with a tiny screen size, though, has been a challenge. He said he's seen screen shots of other apps in development where the font size is too small or the colors don't have enough contrast.
Apple is beginning to accommodate app developers - sort of. It has invited developers to travel to Apple headquarters in Cupertino, Calif., to try out their apps on real Apple Watches. For Herbert, that means flying to California from his home in Collegeville, Pa.
Once he's got the look right, Herbert will have to wait for his app to be approved, and the company has offered little information about the process.
An Apple spokesman declined to discuss the app approval process except to say no Watch apps would be shown in the Apple Store until after the device goes on sale.
Bigger companies working directly with Apple are more confident, but even some of them are having issues. Target boasts that its app will help guide people through stores, but the feature won't be ready by launch.
An uncertainty for almost everyone is what users will want in a smartwatch. Executives at Fandango, the movie ticket buying service, think they know one answer. Its Apple Watch app will display purchased movie tickets with a countdown clock before the movie begins - aimed, for instance, at families eating dinner at the mall before the show.
"It's a watch, and Fandango is well-suited to be aligned with the notion of time," said company President Paul Yanover.
About 50 percent of Fandango sales come from its mobile apps, which have been downloaded 45 million times. Ticket-buying won't come to Watch soon, though. The Los Angeles company plans to gauge how users like the original ideas before developing more.
Some companies, with big brand names and tech industry clout, don't seem worried or impatient.
Asked on stage at a tech industry event last week what communications app Snapchat might look like on Apple Watch, the Los Angeles startup's chief executive, Evan Spiegel, said that he hopes to design something but that it won't come before he "hangs out" with the device.
"If you have your phone with you ... you probably want to watch photos and videos on the biggest screen you have around you," he said. "I don't think the best solution is repurposing our app for a smaller screen; it's probably a new, innovative experience."
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