How apps stay on top in the App Store

Staying in the rarified Top 25 ranking on Apple's App Store is a bit of mad science for companies like Rovio, the makers of Angry Birds.

Apple has its own, closely guarded algorithm for determining where an application lands. There are, or course, other forces at work that push apps into popularity--such as news stories about the apps, or the good fortune of an app being featured by Apple. But with a combination of luck, timing, marketing, and savvy development, small companies like Rovio have created their own tool kits for staying on top.

Of course, it helps if you have an addictive game such as Angry Birds, with a nice movie tie-in like the recently released animated film "Rio." But fun, bird-based projectile games aside, there are tricks and strategies for making it onto Apple's list and staying there, such as formulating a constant stream of updates, adjusting the price tag, and giving users a way to spread the word about the app.

"You have to think about these things from the inception of the game," said Phil Larsen, marketing director for Halfbrick Studios. "You need to say 'we're going to make this game, and it's got to have these particular features and longevity.'"

Halfbrick's hit game, Fruit Ninja, which was released a little more than a year ago, vaulted the company into fame, with the game holding its place at, or very near, the top of Apple's charts in multiple countries since its release. So far its 99 cent iPhone versions have brought in more than 6 million downloads from Apple, and big volumes from other platforms like Android and Windows Phone. Halfbrick is currently cooking up a quick-play version for Facebook that's likely to further augment sales on those other platforms, as it has done for developers such as Zynga and PopCap Games.

Fruit Ninja has users swiping their finger across the screen to cut incoming fruit, all the while avoiding bombs that get thrown into the mix. Along with the version for the iPhone, the company also makes an HD version for iPad users, which also sits near the top of Apple's charts.

Larsen, who joined the company to direct its marketing efforts when it started publishing its own titles, says that a big part of the game's success is that it was designed to be easy to pick up and play, and would keep people coming back to it because of that. "Its almost reminiscent of old card games," Larsen said. "It's addictive and people like playing, yet the core gameplay is satisfying."

Even so, there's been work involved in keeping that momentum going with new sales. A necessary addition to the longevity of that gameplay, Larsen said, were social features to give the game a footprint even after players were done playing.

"Social networking, uploading features, challenging friends--all those kinds of things keep that going socially," Larsen said. In Fruit Ninja's case, the company makes use of both OpenFeint and Apple's Game Center, which are built into the game to include features like friends lists, challenges, and leaderboards.

With OpenFeint specifically, Halfbrick takes advantage of its app discovery service to help introduce users to the company's other games. This is simply a page with links and descriptions of those titles, but it can provide a faster route to those titles than expecting users to dig around on the App Store or trek to a developer's site. Halfbrick also uses it to alert users about updates, which the company releases about once a month, adding new content to reignite interest and keep buyers coming back for more.

Nongames
All this is well and good for games, but where does it leave other types of applications? One notable success story is Penultimate, a notebook application for the iPad that's hung near the top of the charts since its release a year ago. The software, created by developer Ben Zotto, fills a void left by the software that ships with the iPad. Zotto's application lets people write with their fingers, or an iPad compatible stylus, turning the iPad into a big digital notebook. Zotto points to this as one of the big reasons for its success.

"If you're selling something that solves problems for users, they're going to be happy with that," Zotto said in a phone interview last week. "The iPad is this futuristic thing that can bring back speed and usefulness for handwritten stuff--at work and at home--and there are enough people using it that way that the value proposition really resonates with them."

Zotto said sales from the app now support him full-time, as well as affording him ways to expand his operation, including a contractor who handles community management, and another person who does design work.

With that success in the bag, Zotto noted that the App Store for iPad has changed considerably since he first released the app, and that the results would likely not be the same if the app were to come out today. "The free boost you could get by being really early in the ecosystem has mostly gone away," Zotto said. "Now there's traditional marketing, where you have this large marketplace. Maybe Apple features you, but in general you kind of have to go out there and tell people."

Zotto said his plan so far has centered around timely updates that add features and fix bugs, thus giving users a reason to come back to use it. Zotto noted that there's great care involved there, so that when users see an update from you, they'll know to expect it will be filled with new features or improvements. "I learned early on that a bug-fix-only release is dangerous territory," Zotto said. "Though to be clear, if I had something where I was losing user data, of course I'd fix that right away."

Changing the game
Of course, strategizing is a tricky business; Apple likes control. Nowhere is this more apparent than in the App Store, the one place where iPhone, iPod Touch, and iPad users can download and purchase applications the company has approved.

Much like Apple's retail stores, and iTunes, from which it's an offshoot, the App Store represents the company's grand vision of how commerce should work. There are virtual store shelves, as well as a section curated by Apple. But the real heartbeat of it all, and where things still feel like the Wild West, is the realm of the top charts--the home, at any given time, of the hottest 300 free applications and the hottest 300 paid. Once on one of these lists, a good app can continue to make its way up, because a new--and large--group of users is now seeing it. That kind of power also makes these lists a big business target for those with the top in mind.

In late April, several third-party tracking services noticed that Apple changed its ranking algorithm, affecting the placement of some applications. Apple has not discussed--or even verified--that changes were made, but based on how certain applications moved, it appeared to be a reweighting of the categories, giving the top applications in certain categories higher placement in the total rankings than the top apps from another.

Krishna Subramanian, co-founder of Mobclix--an analytics and ad-exchange network for developers and publishers--keeps a close watch on rankings and the mobile advertising market, and compared the move to Google rejiggering its search algorithm.

"You're going to start seeing some of the app ranking optimization," Subramanian said in a phone interview with CNET last week. "New metrics that are possibilities include session times, daily active users, where those users are from, the number of downloads, and what devices they're on."

The reasoning behind the change is said to relate to Tapjoy, an advertising network that's become a center of controversy in recent weeks, after claiming that Apple was rejecting apps that make use of its program. Tapjoy and Flurry, two separate companies, offer services for developers to get a head start for their free applications with paid-for installs. Developers and publishers can pay to have an app promoted using this system.

Tapjoy specifically has a rewards network developers can put into their games to get revenue from actions within games. This makes up a part of an advertising platform that can push a particular game into the eyeline of users with apps that are a part of the network. Flurry has a similar service called AppCircle that can figure out what kinds of users would likely enjoy or use your application, and push out promotion to apps in the network that would coincide. In Tapjoy's case, the company claims such programs can push more than 100,000 new downloads a day for those who buy in to the system.

Some developers with free apps use such services to push their creations into the public eye, as well as to keep momentum going. That includes DistinctDev, which implemented Tapjoy's services on the free version of The Moron Test, its hit game that's managed to stay on Apple's top charts for the better part of two years. That free version, creator Berkeley Malagon explained in a phone interview, was there specifically to drive users to the paid one.

"We've used Tapjoy as one of the mechanisms for rankings pushings and strategically getting to certain numbers, and I think that's fine, but it's something we do rarely," Malagon said. "It's something we understand is second place to having an awesome game."

Malagon also noted that using such systems isn't necessarily a good thing in the long run. "There's no way around having to have a good game. If you have a crappy game, you can push it to the top, but it will fall out and you won't make any money. There's a lot of controversy about Tapjoy and gaming the system, but it's not sustainable to have a bad app and push it up there."

Mobclix's Subramanian suggests that if Apple eventually rids the App Store of such tactics entirely, most developers and publishers will refocus their efforts into other forms of advertising, which is what many end up doing anyway, after reaching a certain threshold of visibility. "Once an app takes the top of the App Store by using incentive-based downloads, they would start doing regular media buys, and there you start seeing organic downloads," Subramanian said.

Whether Apple eventually moves to block Tapjoy and others like it, something that remains a certainty is that all of this is not an exact science. That much can be seen with games like Tiny Wings, a one-man effort by developer Andreas Illiger that's on the shortlist of applications to have temporarily dethroned Angry Birds, and to have managed to stay nipping at that longtime favorites heels long after release. The game follows a similar formula to others mentioned in this article, with quick pick-up-and-play mechanics and plenty of social hooks, including Apple's Game Center and OpenFeint.

Where some of the interest lies going forward are the kind of mechanisms Apple puts in place to help developers continue momentum after a launch, and how other companies will step up to fill that need. Apple has arguably laid the foundation with features like Genius to suggest applications people might like, as well as myriad ways to browse, search, and explore applications. Ultimately though, it's really up to developers to give customers a reason to invest in an app in the first place.

"The basic lesson--as in mobile software, as in software, as in all consumer products--is that if you have a compelling product. It's the best hedge against dropping off into nothingness," Zotto said. "The overall message is, "If you're selling something that solves problems, people are going to be happy about that."