The global app market will hit $51 billion in revenue in 2016, according to a new forecast by app-analytics firm App Annie. The firm’s analysts believe the market will climb to $100 billion by 2020, thanks in large part to increased mobile-device use in developing nations such as India and Mexico. The burgeoning market for mobile apps is something of a double-edged sword for developers. On one hand, who wouldn’t want a big market for their product? As demonstrated by apps such as Dong Nguyen’s “Flappy Bird,” the opportunities for success aren’t limited to huge software developers with substantial budgets and staff: an independent developer with the right idea (and more than a little luck) can also profit enormously. But a crowded market also makes it that much harder for an individual app to stand out. A 2015 study by Adobe found that the average app fades after roughly six months—a narrow window for widespread adoption. For mobile games, according to another report by App Annie, one of the more popular categories of apps, that lifespan is 17 weeks, or just over four months. And the timeframe is shrinking. “Compared to just three years prior, this is a remarkably slim window in which to generate downloads,” App Annie’s report added. “For games released in 2012, average time to maturity was over 10 times longer than it was for those released in 2015.” For developers, the potential market will only grow over the next several years—but so will the problems. Building an innovative, polished product is just step one; you also have to market it.