A new report has revealed that mobile marketing costs and downloads have dropped slightly in May due to seasonal slowdowns, app store changes and smarter advertising.

The cost per loyal user (CPLU) decreased 10% to reach $2.47, with overall downloads declining 17% to reach 6.7 million for the month.

The cost per install index (CPI) decreased to $1.46 on iOS, a 31% fall since April, while CPIs on Android increased to $2.33, a 12% rise month over month.

According to the Fiksu Indexes, the cost per launch (CPL) decreased 31% on iOS to $0.28, while CPLs on Android decreased 14% to $0.30.

Fiksu CEO Micah Adler said: "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.

"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."

Fiksu said mobile has undergone a shift from the past two months and brands are taking suggestions from offline and web advertising as well as building audiences on mobile utilising more detailed information.