in app purchase audio files

We selling pre-record attraction audio guide through our app, when we first submit for review we have been told that because the audio files would be use on the cunsumers' device therefore it classified as service on the apple platform we can not direct the payment process to third party, the payment has to be make through Apple. but recently we have just fund out that one of the app has very similar functions but they can sell their audio files through wechat payment system. can anyone tell me why is this?


The App is can be fund through the link below:


https://itunes.apple.com/cv/app/yu-yin-dao-you-dao-ting-tu-shuo/id1035532946?mt=8


there first audio always free all others are chargeable.

in app purchase audio files
 
 
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