Apple defended the fees it charges developers to sell their content and products on its App Store, commissioning a study which showed its rates were similar to rival offerings.

The study, which was conducted by the Analysis Group, is in response to scrutiny the iPhone maker faced in recent months over its App Store policies.

It provided a comparison of App Store commission with 37 other digital and e-commerce platforms.

“The commission rates charged by digital marketplaces most similar to the App Store, such as other app stores and video game digital marketplaces, are generally around 30 per cent,” the research found.

It cited Microsoft, Google, Amazon and Samsung as also charging 30 per cent, however there were some notable exceptions on both ends of the scale.

For example, Analysis Group found certain Chinese marketplaces, including the Xiaomi MIUI app store and Huawei’s AppGallery, often charged 50 per cent or more.

The Epic Games Store, on the other hand, charged 12 per cent commission.

Probes
With the study, Apple appears to be digging its heels in, as it faces scrutiny in Europe and the US over its App Store policies.

The European Commission opened a probe in June exploring if Apple’s App Store breached competition rules, while a similar investigation  is underway in the US.

Apple CEO Tim Cook is expected to give testimony to the US Congress next week on the matter.

Microsoft president Brad Smith previously weighed in, urging more scrutiny of app stores in general.

Apple already ceded some ground to App Store developers, giving them more power to challenge guidelines following a spat with Basecamp over its Hey email app.