Gaming led worldwide app downloads for iOS and Google Android in 2015, according to an annual report from app-analytics firm App Annie (PDF). On iOS, photo and video apps came in second place, by total number of downloads, followed by entertainment, social networking, lifestyle, utilities, and productivity. Music, education, and travel rounded out the top 10. Things were a little different on Google Play, where tools came in second place and communication in third, followed by photography, entertainment, social, personalization, and music & audio. Productivity and media & video came in ninth and tenth, respectively. The enduring popularity of mobile games presents an opportunity for developers in that space—as well as some significant risks. App Annie estimated the time to maturity for new games at just over 17 weeks in 2015. “Compared to just three years prior, this is a remarkably slim window in which to generate downloads,” the report added. “For games released in 2012, average time to maturity was over 10 times longer than it was for those released in 2015.” That short timeframe creates some issues when it comes to marketing. “It also has significant ramifications for portfolio management, with most publishers requiring more frequent releases to maintain the momentum that may have been sustained by a single title in previous years.” Fortunately, the app market is more than games. Surely apps for other categories, such as productivity, have a longer “lifespan,” right? According to data released in mid-2015 by Adobe, the answer is yes—but not by much. The software company showed that the average app faded after roughly six months. That puts pressure on developers to rack up a large number of downloads as soon as possible after their app’s release. And that’s not just a matter of marketing; it also means building a solid product that’s as bug-free as possible.