The initial rush to download the latest game app is great for video game makers. But video game apps have to keep customers playing — and paying — after the new-game novelty wears off, and even the top games have had a hard time growing revenue.
In fact, the top 10 games launched in 2016 by revenue in Apple’s U.S. App Store all saw a drop in sales at some point in the past year, according to app research company Sensor Tower.
When it launched, Pokémon Go had hordes of people roaming the streets looking to capture characters from the game in what purported to be an augmented reality. But daily Pokémon Go use peaked in August, and its in-app revenue in the U.S. topped out at $50.6 million in the App Store in July, the month the game launched.
Meanwhile, Supercell’s Clash Royale didn’t have as eminent a start as Pokémon, but it has managed to reverse revenue loss through a series of in-game events and updates based on trends and user feedback.
These updates have kept users spending on small transactions within the game — nearly $40 million last month. Niantic’s Pokémon Go has also held holiday events and released updates, but so far these have not managed to reverse user defection.
Similarly, NBA Live Mobile Basketball saw a spike in revenue thanks to a March Madness event, but that wasn’t enough to keep people’s heads in the game.
Super Mario Run, like Pokémon Go, launched with a loyal fan base who wanted to play the latest Mario reboot. Despite its popular advantage, Super Mario Run’s single in-app purchase of $9.99, which unlocks all its levels, proved too steep for many customers. Clash Royale and Pokémon Go have had better luck getting people to pay smaller amounts over longer periods of time.
To be sure, it’s not unusual for big, well-funded games to get a big revenue jump at launch, which means it’s only more likely that it will level off. But it’s a sign of just how difficult it is to keep consumers’ interest in app video games.
This article originally appeared on Recode.net.