Marketers got a rare break in marketing costs for mobile games last month.

The Fiksu Cost Per Loyal User Index, which measures the cost of acquiring a loyal user for brands who actively market their apps, shows that costs were down in May 10 percent, at $2.47 a user. The mobile marketing company’s Fiksu Indexes note that adjustments to the App Store last month, which had Apple moving from generated lists to curated ones, likely contributed to this dip. Fiksu gets its information from 3.5 billion app installs and 5.4 trillion marketing events tracked across 1.7 billion devices.

Downloads were also down for the month. The App Store Competitive Index tracks the average aggregate daily downloads of the top 200 free apps, and it shows a decrease of 17 percent from the previous month, down to 6.7 million. Fiksu points to brands exploring new tactics for marketers, with a focus on smarter targeting.

Fiksu’s Cost Per Install Index, which figures the cost per app install directly tied to ads, is also down for May. It fell to $1.46 on iOS, a decrease of 31 percent from April and 3 percent since last year. But it climbed a bit on the Android side, up 12 percent from last month and 93 percent from last year.

“While we have seen seasonal slowdowns of app marketing during the summer months in prior years, May’s results also reflect brands implementing more precise audience segmentation,” said Micah Adler, CEO of Fiksu, in a statement. “While Facebook has been a preferred tool to reach mobile audiences, rising CPIs in 2015 has caused some marketers to look for ways to reduce costs and focus their spend on the right groups of users. As we predicted last month, smarter spending across the ecosystem will, in due course, cause loyalty rates of app users to improve.”